16 Pitch Stub Acme Threading Tools -Hill Industrial Tools - acme threading tool

PropertyAusteniticMartensiticFeriticPHDuplexCorrosion ResistanceExcelentFairGoodGoodExcelent++Magnetic?NoYesYesNoNoHeat Treatable?NoYesNoYesNoMachinability35-75%40-75%40-75%40-50%20-30%Hardness~180Max 600~200Max 400~280Strength [Kpsi]~90~120~100~200~250Cr16-20%11-14%11-18%14-17%18-30%Ni6-15%0-2%0-1%4-8%4-7%Mo2-4%-0-1.2%1.5-2.5%0-5%On which stainless steel group do you want to learn?AusteniticFerriticMartensiticPHDuplexAustenitic Stainless SteelAustenitic is the most popular family of Stainless steel and is characterized by high Chromium content, up to 20%, with the addition of Nickel of up to 15%. Due to the high nickel content, It has better corrosion resistance, but it is harder to machine. It lacks strength and hardness compared to other types of Stainless Steel. Most alloys in this series have low carbon content, below 0.1%. This makes them ductile; therefore, chip control and BUE are significant concerns for machinists. Alloys with the suffix “L” (For example 304L / 316L), have minimal carbon content (Usually 0.03%), which makes them even more problematic for machining.Main Features of Austenitic Stainless Steel:Corrosion resistance: Excellent.Heat Treatable: No.Magnetic: No.Chromium content: 16-20.0%Nickel content: 6-15%Molybdenum content: 2-4%Typical max Hardness: 180 HBTypical Tensile Strength: 90 [Kpsi]Popular materials: 303, 304, and 316.Typical parts: Valves and fasteners in a chemically harsh environment, Marine, Medical.Machinability of Austenitic Stainless-Steel 300 series (303/304/316)Main Problems:High cutting forces.Heat.Build up Edge – Workpiece material sticking to the cutting edge.Notch Wear (Vg) – High wear developing at the depth of cut line.Higher Nickel (Ni) and Molybdenum (Mo) content decrease machinability.Best Practice:Use TiAlN PVD grades or thin-layer CVD grades.Use a good supply of coolant directed to the cutting edge.Avoid machining at a constant depth of cut to reduce the risk of Vg (Notch Wear).Grades WizardCarbide Grades for Stainless SteelsSpeed and Feed CalculatorCutting Speeds for Stainless SteelMain Materials:SAE 303 (Din X10CrNiS18-10) is considered a “Free-Cutting” material and is the easiest to machine Austenitic Stainless Steel. This is achieved by adding Sulfur and Selenium to 304. However, it comes with the “price” of lower corrosion resistance.SAE 304 (Din X5CrNi18-10) is the most popular and versatile Stainless Steel type. It has good corrosion resistance and still maintains fair machinability. It is easier to machine and cheaper compared to 316.SAE 316 (Din X5CrNiMo17-12-2) is the most popular stainless steel for harsh environments. The main difference between 316 and 304 stainless steel is that 316 contains an increased amount of molybdenum. This additive gives 316 very good heat and corrosion resistance. However, it is the most difficult to machine among the commonly used stainless steels.Cutting Speeds Recommendations for 300 SeriesSAEMachinabilityTurningMilling30375%920 SFM280 mm/min460 SFM140 mm/min30440%600 SFM 180 mm/min330 SFM 100 mm/min31636%500 SFM 150 mm/min260 SFM 80 mm/minMartensitic Stainless SteelIt is the second group in terms of popularity, characterized by Chromium content of up to 14% with almost no nickel. This group of alloys can be heat-treated and hardened, therefore providing higher strength. However, it has corrosion resistance only in atmospheric conditions and cannot be used in harsh environments.Main Features of Martensitic Stainless Steel:Corrosion Resistance: Moderate.Magnetic: Yes.Heat Treatable: Yes.Chromium content: 11-14%Nickel content: 0-2%Molybdenum content: None.Typical max Hardness: 600 HB (After heat treatment).Typical Tensile Strength: 120 [Kpsi].Popular materilas: SAE 420 / 440.Typical parts: Razor blades, Surgical instruments, and other parts that require higher strength but are less critical in terms of corrosion resistance.Ferritic Stainless SteelFerritic stainless steel materials have a Chromium content of up to 18% with almost no nickel. They have better corrosion resistance than Martensitic grades but less than Austenitic ones. It cannot be hardened by heat treatments.Main Features of Ferritic Stainless Steel:Corrosion Resistance: Good – Moderate.Heat Treatable: No.Magnetic: YesChromium content: 11-18%Nickel content: 0-1%Molybdenum content: 0-1.25%.Typical max Hardness: 200 HB.Typical Tensile Strength: 100 [Kpsi].Popular grades: 409 / 430.Typical parts: Auto exhausts, grills, coffee machine parts, and other household appliances.Machinability of Ferritic/Martensitic Stainless-Steel 400 seriesMartensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

Machining304stainless steel

Turning centers are much easier to integrate with both simple (bar feeders) and complex (gantry robots) automation than grinders, and it is easier to find qualified people to operate turning centers. However, grinding is still the operation of choice for components requiring the tightest of tolerances (±0.0002 in.). The fine finish of a grinding operation at these Ra levels cannot be reproduced even by the best hard turning operation. A spiral feed line will always appear on the part with a single-point turning tool as opposed to a multipoint tool like a grinding wheel.

“Xcel is based on an existing insert style, but it has a unique corner configuration. It has a very shallow entry angle, which thins out the chip, allowing higher feed rates than in normal hard part turning,” said Andrews. “Instead of 0.004 to 0.006 in. per revolution, these inserts can be run at 0.016 per revolution.”

“One nice thing about the mixed ceramics, however, is that they can handle soft and hard materials, whereas CBN inserts don’t work particularly well in softer material,” said Andrews.

“When this happens, people often make the mistake of moving to a different grade, repeating the process, and causing the failure to occur even more quickly,” said Andrews.

“No two jobs are identical, and no two shops are identical,” said Geisel. “As the technology grows, more and more shops will be able to take advantage of the benefits that come with hard part turning.”

Stainless Steelmachinability chart

CBN tools have four properties that enable them to cut hard materials at high metal removal rates: high strength, high hardness, good thermal conductivity, and abrasion resistance. This is what enables them to cut hardened materials faster and deeper than carbide inserts.

Keep up to date with the latest news, events, and technology for all things metal from our pair of monthly magazines written specifically for Canadian manufacturers!

Carbide inserts, the standard choice for most machining operations, can be used at the lower range of hardness (45 to 50 HRC), but at much lower cutting speeds. As materials get harder, cubic boron nitride (CBN) is added to the equation.

303stainless steelmachinability

PREMIUM MEMBERSHIP- Ads Free Browsing- Advanced Calculator Options- Quick Access Favorites BarFor Just 2$ / MonthLearn More

“CBN is the first choice above 55 HRC,” explained David Andrews, product and application specialist for Sandvik Coromant Canada. “If a shop is hard part turning in high volumes, we will always recommend that CBN be used.”

Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

316 stainless steelcutting speed

Stainless steels, as their name suggests, are a group of steel alloys with a shiny appearance and good corrosion resistance. The base element (70-80%) is Iron (Fe) with a minimum of 10.5% Chromium; most grades will have additional alloying elements such as nickel (Ni) and molybdenum (Mo).types of Stainless SteelPropertyAusteniticMartensiticFeriticPHDuplexCorrosion ResistanceExcelentFairGoodGoodExcelent++Magnetic?NoYesYesNoNoHeat Treatable?NoYesNoYesNoMachinability35-75%40-75%40-75%40-50%20-30%Hardness~180Max 600~200Max 400~280Strength [Kpsi]~90~120~100~200~250Cr16-20%11-14%11-18%14-17%18-30%Ni6-15%0-2%0-1%4-8%4-7%Mo2-4%-0-1.2%1.5-2.5%0-5%On which stainless steel group do you want to learn?AusteniticFerriticMartensiticPHDuplexAustenitic Stainless SteelAustenitic is the most popular family of Stainless steel and is characterized by high Chromium content, up to 20%, with the addition of Nickel of up to 15%. Due to the high nickel content, It has better corrosion resistance, but it is harder to machine. It lacks strength and hardness compared to other types of Stainless Steel. Most alloys in this series have low carbon content, below 0.1%. This makes them ductile; therefore, chip control and BUE are significant concerns for machinists. Alloys with the suffix “L” (For example 304L / 316L), have minimal carbon content (Usually 0.03%), which makes them even more problematic for machining.Main Features of Austenitic Stainless Steel:Corrosion resistance: Excellent.Heat Treatable: No.Magnetic: No.Chromium content: 16-20.0%Nickel content: 6-15%Molybdenum content: 2-4%Typical max Hardness: 180 HBTypical Tensile Strength: 90 [Kpsi]Popular materials: 303, 304, and 316.Typical parts: Valves and fasteners in a chemically harsh environment, Marine, Medical.Machinability of Austenitic Stainless-Steel 300 series (303/304/316)Main Problems:High cutting forces.Heat.Build up Edge – Workpiece material sticking to the cutting edge.Notch Wear (Vg) – High wear developing at the depth of cut line.Higher Nickel (Ni) and Molybdenum (Mo) content decrease machinability.Best Practice:Use TiAlN PVD grades or thin-layer CVD grades.Use a good supply of coolant directed to the cutting edge.Avoid machining at a constant depth of cut to reduce the risk of Vg (Notch Wear).Grades WizardCarbide Grades for Stainless SteelsSpeed and Feed CalculatorCutting Speeds for Stainless SteelMain Materials:SAE 303 (Din X10CrNiS18-10) is considered a “Free-Cutting” material and is the easiest to machine Austenitic Stainless Steel. This is achieved by adding Sulfur and Selenium to 304. However, it comes with the “price” of lower corrosion resistance.SAE 304 (Din X5CrNi18-10) is the most popular and versatile Stainless Steel type. It has good corrosion resistance and still maintains fair machinability. It is easier to machine and cheaper compared to 316.SAE 316 (Din X5CrNiMo17-12-2) is the most popular stainless steel for harsh environments. The main difference between 316 and 304 stainless steel is that 316 contains an increased amount of molybdenum. This additive gives 316 very good heat and corrosion resistance. However, it is the most difficult to machine among the commonly used stainless steels.Cutting Speeds Recommendations for 300 SeriesSAEMachinabilityTurningMilling30375%920 SFM280 mm/min460 SFM140 mm/min30440%600 SFM 180 mm/min330 SFM 100 mm/min31636%500 SFM 150 mm/min260 SFM 80 mm/minMartensitic Stainless SteelIt is the second group in terms of popularity, characterized by Chromium content of up to 14% with almost no nickel. This group of alloys can be heat-treated and hardened, therefore providing higher strength. However, it has corrosion resistance only in atmospheric conditions and cannot be used in harsh environments.Main Features of Martensitic Stainless Steel:Corrosion Resistance: Moderate.Magnetic: Yes.Heat Treatable: Yes.Chromium content: 11-14%Nickel content: 0-2%Molybdenum content: None.Typical max Hardness: 600 HB (After heat treatment).Typical Tensile Strength: 120 [Kpsi].Popular materilas: SAE 420 / 440.Typical parts: Razor blades, Surgical instruments, and other parts that require higher strength but are less critical in terms of corrosion resistance.Ferritic Stainless SteelFerritic stainless steel materials have a Chromium content of up to 18% with almost no nickel. They have better corrosion resistance than Martensitic grades but less than Austenitic ones. It cannot be hardened by heat treatments.Main Features of Ferritic Stainless Steel:Corrosion Resistance: Good – Moderate.Heat Treatable: No.Magnetic: YesChromium content: 11-18%Nickel content: 0-1%Molybdenum content: 0-1.25%.Typical max Hardness: 200 HB.Typical Tensile Strength: 100 [Kpsi].Popular grades: 409 / 430.Typical parts: Auto exhausts, grills, coffee machine parts, and other household appliances.Machinability of Ferritic/Martensitic Stainless-Steel 400 seriesMartensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

Easily access valuable industry resources now with full access to the digital edition of Canadian Fabricating & Welding.

“Being successful in business is about more than simply machining a part for shops today,” said Geisel. “Every time unfinished parts are sent out for heat-treating, production of those particular parts stops, a purchase order needs to be generated, and you wait on shipping. Conversely, if you bring in stock that has already been hardened, you don’t have these production delays and extra office costs.”

Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

Chip removal is one of the major problem areas associated with hard part turning. During the machining process, a long, thin, ribbon-like chip is produced. Some CBN inserts can also have a chip breaker, which can aid in chip formation and removal, eliminating the birdnesting that is common in hard part turning.

Machining stainless steelon lathe

While mixed ceramic and cermet inserts have their place in the 45- to 55-HRC range in certain types of turning, the hardest materials require CBN.

“If you are machining a hard part with carbide, you will be limited to about 60 SFM; however, when using CBN tooling, you can reach between 450 and 650 SFM,” explained Steve Geisel, product manager for Iscar Tools Canada. “It’s not even close at these high hardness levels.”

Technology advances in both machine tools and cutting tools are enabling manufacturers to turn a prehardened part faster and more efficiently.

Stainless Steel is the 2nd most popular materials group (After Steel) in machine shops. Machinability of Stainless Steel ranges from free-cutting grades like 430F and 303, having a machinability of 75%, and up to challenging grades like 316, with a Machinability of 36%.Learn MoreMachinability Chart

DiPaolo sells and services premium machine tools across North America. Contact us for your next 3, 4, or 5 axis milling, turning or grinding project.

Do you want to reach technical audience in the Machining Industry? Look no further! We have a massive audience of professionals, and our precise targeting ensures your message gets across exactly where it needs to be. Learn More

The below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

Martensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

“We have seen that standard-pressure coolant use does not really give any benefits,” said Andrews. “High-pressure coolant, on the other hand, can create 20 to 25 percent extra tool life in good conditions.”

“CBN tools improve efficiency, reduce scrap rates, and increase part quality,” said Geisel. “Because of the hard microstructure of CBN, cutting edges last longer.”

In addition to the machining process benefits, turning prehardened material also can save a shop time and money in other ways. Roughing a part, shipping it to a heat-treater, and waiting for it to return takes time and costs money.

It is a growing trend in the automotive industry to hard turn a part either to completion, or to hard turn during the roughing stage and then grind to the final surface finish (Ra factor) requirements. In the production of aerospace landing gears, which typically are 55 HRC, hard turning has been used for many years. A more recent trend, however, is the hard turning of bearing races, which have curved surfaces that often can be profiled faster and more economically on a turning center than on a grinder.

Insert selection is important in every turning operation, but in hard turning it is one of the first factors that needs to be considered.

The shallow entry angle spreads the work over a larger area of the insert. This spreads the heat out over a larger area, and also spreads the wear out over a larger area. This even wear pattern lengthens tool life, but, because of the shallow entry angle, the part needs to have open features or an undercut to work with this insert. And, just like a high-feed milling operation, stability in the setup is important to get the best results.

PREMIUM MEMBERSHIP- Ads Free Browsing- Advanced Calculator Options- Quick Access Favorites BarFor Just 2$ / MonthLearn More

These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

316 stainless steelvs 304

Hardened ferrous metals, including 4340, 8620, M2, and T15; abrasive ferrous metals, such as pearlistic gray cast iron; heat-resistant alloys; and superalloys all are candidates for CBN.

“The CBN has to be matched to the workpiece that you are machining,” said Geisel. “The specific grade will depend on whether the turning operation is constant or interrupted, and also on the material being machined. Hardened exotic materials, for example, require a different CBN grade than hardened carbon steels or hardened stainless steels.”

The most common wear mechanism in hard part turning is crater wear to the insert. When setting up a job for the first time, it is important to keep an eye on the insert for this type of wear. During this fine-tuning of the process, it is important to determine how the insert will wear and how long it should be used.

Insert selection is important in every turning operation, but in hard turning it is one of the first factors that needs to be considered. Asking a few questions can help you streamline the selection process:

Does316 stainless steelwork harden

Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

On which stainless steel group do you want to learn?AusteniticFerriticMartensiticPHDuplexAustenitic Stainless SteelAustenitic is the most popular family of Stainless steel and is characterized by high Chromium content, up to 20%, with the addition of Nickel of up to 15%. Due to the high nickel content, It has better corrosion resistance, but it is harder to machine. It lacks strength and hardness compared to other types of Stainless Steel. Most alloys in this series have low carbon content, below 0.1%. This makes them ductile; therefore, chip control and BUE are significant concerns for machinists. Alloys with the suffix “L” (For example 304L / 316L), have minimal carbon content (Usually 0.03%), which makes them even more problematic for machining.Main Features of Austenitic Stainless Steel:Corrosion resistance: Excellent.Heat Treatable: No.Magnetic: No.Chromium content: 16-20.0%Nickel content: 6-15%Molybdenum content: 2-4%Typical max Hardness: 180 HBTypical Tensile Strength: 90 [Kpsi]Popular materials: 303, 304, and 316.Typical parts: Valves and fasteners in a chemically harsh environment, Marine, Medical.Machinability of Austenitic Stainless-Steel 300 series (303/304/316)Main Problems:High cutting forces.Heat.Build up Edge – Workpiece material sticking to the cutting edge.Notch Wear (Vg) – High wear developing at the depth of cut line.Higher Nickel (Ni) and Molybdenum (Mo) content decrease machinability.Best Practice:Use TiAlN PVD grades or thin-layer CVD grades.Use a good supply of coolant directed to the cutting edge.Avoid machining at a constant depth of cut to reduce the risk of Vg (Notch Wear).Grades WizardCarbide Grades for Stainless SteelsSpeed and Feed CalculatorCutting Speeds for Stainless SteelMain Materials:SAE 303 (Din X10CrNiS18-10) is considered a “Free-Cutting” material and is the easiest to machine Austenitic Stainless Steel. This is achieved by adding Sulfur and Selenium to 304. However, it comes with the “price” of lower corrosion resistance.SAE 304 (Din X5CrNi18-10) is the most popular and versatile Stainless Steel type. It has good corrosion resistance and still maintains fair machinability. It is easier to machine and cheaper compared to 316.SAE 316 (Din X5CrNiMo17-12-2) is the most popular stainless steel for harsh environments. The main difference between 316 and 304 stainless steel is that 316 contains an increased amount of molybdenum. This additive gives 316 very good heat and corrosion resistance. However, it is the most difficult to machine among the commonly used stainless steels.Cutting Speeds Recommendations for 300 SeriesSAEMachinabilityTurningMilling30375%920 SFM280 mm/min460 SFM140 mm/min30440%600 SFM 180 mm/min330 SFM 100 mm/min31636%500 SFM 150 mm/min260 SFM 80 mm/minMartensitic Stainless SteelIt is the second group in terms of popularity, characterized by Chromium content of up to 14% with almost no nickel. This group of alloys can be heat-treated and hardened, therefore providing higher strength. However, it has corrosion resistance only in atmospheric conditions and cannot be used in harsh environments.Main Features of Martensitic Stainless Steel:Corrosion Resistance: Moderate.Magnetic: Yes.Heat Treatable: Yes.Chromium content: 11-14%Nickel content: 0-2%Molybdenum content: None.Typical max Hardness: 600 HB (After heat treatment).Typical Tensile Strength: 120 [Kpsi].Popular materilas: SAE 420 / 440.Typical parts: Razor blades, Surgical instruments, and other parts that require higher strength but are less critical in terms of corrosion resistance.Ferritic Stainless SteelFerritic stainless steel materials have a Chromium content of up to 18% with almost no nickel. They have better corrosion resistance than Martensitic grades but less than Austenitic ones. It cannot be hardened by heat treatments.Main Features of Ferritic Stainless Steel:Corrosion Resistance: Good – Moderate.Heat Treatable: No.Magnetic: YesChromium content: 11-18%Nickel content: 0-1%Molybdenum content: 0-1.25%.Typical max Hardness: 200 HB.Typical Tensile Strength: 100 [Kpsi].Popular grades: 409 / 430.Typical parts: Auto exhausts, grills, coffee machine parts, and other household appliances.Machinability of Ferritic/Martensitic Stainless-Steel 400 seriesMartensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

Milling316 stainless steelspeeds and feeds

Hardened ferrous metals, including 4340, 8620, M2, and T15; abrasive ferrous metals, such as pearlistic gray cast iron; heat-resistant alloys; and superalloys all are candidates for CBN.

Crater wear can be dealt with by reducing cutting data, mainly cutting speed. As the speed is reduced, tool life typically increases.

This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

It is the second group in terms of popularity, characterized by Chromium content of up to 14% with almost no nickel. This group of alloys can be heat-treated and hardened, therefore providing higher strength. However, it has corrosion resistance only in atmospheric conditions and cannot be used in harsh environments.Main Features of Martensitic Stainless Steel:Corrosion Resistance: Moderate.Magnetic: Yes.Heat Treatable: Yes.Chromium content: 11-14%Nickel content: 0-2%Molybdenum content: None.Typical max Hardness: 600 HB (After heat treatment).Typical Tensile Strength: 120 [Kpsi].Popular materilas: SAE 420 / 440.Typical parts: Razor blades, Surgical instruments, and other parts that require higher strength but are less critical in terms of corrosion resistance.Ferritic Stainless SteelFerritic stainless steel materials have a Chromium content of up to 18% with almost no nickel. They have better corrosion resistance than Martensitic grades but less than Austenitic ones. It cannot be hardened by heat treatments.Main Features of Ferritic Stainless Steel:Corrosion Resistance: Good – Moderate.Heat Treatable: No.Magnetic: YesChromium content: 11-18%Nickel content: 0-1%Molybdenum content: 0-1.25%.Typical max Hardness: 200 HB.Typical Tensile Strength: 100 [Kpsi].Popular grades: 409 / 430.Typical parts: Auto exhausts, grills, coffee machine parts, and other household appliances.Machinability of Ferritic/Martensitic Stainless-Steel 400 seriesMartensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

“Inserts that have a chip breaker create very small chips similar to those you get if you are machining steel in its normal state,” said Geisel.

At Machining Doctor, our mission is to serve the machining industry as a comprehensive and reliable source of technical information. We strive to be the go-to destination for professionals in the niche seeking information, knowledge, and expertise. Join us and stay ahead of the curve! Learn more

Austenitic is the most popular family of Stainless steel and is characterized by high Chromium content, up to 20%, with the addition of Nickel of up to 15%. Due to the high nickel content, It has better corrosion resistance, but it is harder to machine. It lacks strength and hardness compared to other types of Stainless Steel. Most alloys in this series have low carbon content, below 0.1%. This makes them ductile; therefore, chip control and BUE are significant concerns for machinists. Alloys with the suffix “L” (For example 304L / 316L), have minimal carbon content (Usually 0.03%), which makes them even more problematic for machining.Main Features of Austenitic Stainless Steel:Corrosion resistance: Excellent.Heat Treatable: No.Magnetic: No.Chromium content: 16-20.0%Nickel content: 6-15%Molybdenum content: 2-4%Typical max Hardness: 180 HBTypical Tensile Strength: 90 [Kpsi]Popular materials: 303, 304, and 316.Typical parts: Valves and fasteners in a chemically harsh environment, Marine, Medical.Machinability of Austenitic Stainless-Steel 300 series (303/304/316)Main Problems:High cutting forces.Heat.Build up Edge – Workpiece material sticking to the cutting edge.Notch Wear (Vg) – High wear developing at the depth of cut line.Higher Nickel (Ni) and Molybdenum (Mo) content decrease machinability.Best Practice:Use TiAlN PVD grades or thin-layer CVD grades.Use a good supply of coolant directed to the cutting edge.Avoid machining at a constant depth of cut to reduce the risk of Vg (Notch Wear).Grades WizardCarbide Grades for Stainless SteelsSpeed and Feed CalculatorCutting Speeds for Stainless SteelMain Materials:SAE 303 (Din X10CrNiS18-10) is considered a “Free-Cutting” material and is the easiest to machine Austenitic Stainless Steel. This is achieved by adding Sulfur and Selenium to 304. However, it comes with the “price” of lower corrosion resistance.SAE 304 (Din X5CrNi18-10) is the most popular and versatile Stainless Steel type. It has good corrosion resistance and still maintains fair machinability. It is easier to machine and cheaper compared to 316.SAE 316 (Din X5CrNiMo17-12-2) is the most popular stainless steel for harsh environments. The main difference between 316 and 304 stainless steel is that 316 contains an increased amount of molybdenum. This additive gives 316 very good heat and corrosion resistance. However, it is the most difficult to machine among the commonly used stainless steels.Cutting Speeds Recommendations for 300 SeriesSAEMachinabilityTurningMilling30375%920 SFM280 mm/min460 SFM140 mm/min30440%600 SFM 180 mm/min330 SFM 100 mm/min31636%500 SFM 150 mm/min260 SFM 80 mm/minMartensitic Stainless SteelIt is the second group in terms of popularity, characterized by Chromium content of up to 14% with almost no nickel. This group of alloys can be heat-treated and hardened, therefore providing higher strength. However, it has corrosion resistance only in atmospheric conditions and cannot be used in harsh environments.Main Features of Martensitic Stainless Steel:Corrosion Resistance: Moderate.Magnetic: Yes.Heat Treatable: Yes.Chromium content: 11-14%Nickel content: 0-2%Molybdenum content: None.Typical max Hardness: 600 HB (After heat treatment).Typical Tensile Strength: 120 [Kpsi].Popular materilas: SAE 420 / 440.Typical parts: Razor blades, Surgical instruments, and other parts that require higher strength but are less critical in terms of corrosion resistance.Ferritic Stainless SteelFerritic stainless steel materials have a Chromium content of up to 18% with almost no nickel. They have better corrosion resistance than Martensitic grades but less than Austenitic ones. It cannot be hardened by heat treatments.Main Features of Ferritic Stainless Steel:Corrosion Resistance: Good – Moderate.Heat Treatable: No.Magnetic: YesChromium content: 11-18%Nickel content: 0-1%Molybdenum content: 0-1.25%.Typical max Hardness: 200 HB.Typical Tensile Strength: 100 [Kpsi].Popular grades: 409 / 430.Typical parts: Auto exhausts, grills, coffee machine parts, and other household appliances.Machinability of Ferritic/Martensitic Stainless-Steel 400 seriesMartensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

On which stainless steel group do you want to learn?AusteniticFerriticMartensiticPHDuplexAustenitic Stainless SteelAustenitic is the most popular family of Stainless steel and is characterized by high Chromium content, up to 20%, with the addition of Nickel of up to 15%. Due to the high nickel content, It has better corrosion resistance, but it is harder to machine. It lacks strength and hardness compared to other types of Stainless Steel. Most alloys in this series have low carbon content, below 0.1%. This makes them ductile; therefore, chip control and BUE are significant concerns for machinists. Alloys with the suffix “L” (For example 304L / 316L), have minimal carbon content (Usually 0.03%), which makes them even more problematic for machining.Main Features of Austenitic Stainless Steel:Corrosion resistance: Excellent.Heat Treatable: No.Magnetic: No.Chromium content: 16-20.0%Nickel content: 6-15%Molybdenum content: 2-4%Typical max Hardness: 180 HBTypical Tensile Strength: 90 [Kpsi]Popular materials: 303, 304, and 316.Typical parts: Valves and fasteners in a chemically harsh environment, Marine, Medical.Machinability of Austenitic Stainless-Steel 300 series (303/304/316)Main Problems:High cutting forces.Heat.Build up Edge – Workpiece material sticking to the cutting edge.Notch Wear (Vg) – High wear developing at the depth of cut line.Higher Nickel (Ni) and Molybdenum (Mo) content decrease machinability.Best Practice:Use TiAlN PVD grades or thin-layer CVD grades.Use a good supply of coolant directed to the cutting edge.Avoid machining at a constant depth of cut to reduce the risk of Vg (Notch Wear).Grades WizardCarbide Grades for Stainless SteelsSpeed and Feed CalculatorCutting Speeds for Stainless SteelMain Materials:SAE 303 (Din X10CrNiS18-10) is considered a “Free-Cutting” material and is the easiest to machine Austenitic Stainless Steel. This is achieved by adding Sulfur and Selenium to 304. However, it comes with the “price” of lower corrosion resistance.SAE 304 (Din X5CrNi18-10) is the most popular and versatile Stainless Steel type. It has good corrosion resistance and still maintains fair machinability. It is easier to machine and cheaper compared to 316.SAE 316 (Din X5CrNiMo17-12-2) is the most popular stainless steel for harsh environments. The main difference between 316 and 304 stainless steel is that 316 contains an increased amount of molybdenum. This additive gives 316 very good heat and corrosion resistance. However, it is the most difficult to machine among the commonly used stainless steels.Cutting Speeds Recommendations for 300 SeriesSAEMachinabilityTurningMilling30375%920 SFM280 mm/min460 SFM140 mm/min30440%600 SFM 180 mm/min330 SFM 100 mm/min31636%500 SFM 150 mm/min260 SFM 80 mm/minMartensitic Stainless SteelIt is the second group in terms of popularity, characterized by Chromium content of up to 14% with almost no nickel. This group of alloys can be heat-treated and hardened, therefore providing higher strength. However, it has corrosion resistance only in atmospheric conditions and cannot be used in harsh environments.Main Features of Martensitic Stainless Steel:Corrosion Resistance: Moderate.Magnetic: Yes.Heat Treatable: Yes.Chromium content: 11-14%Nickel content: 0-2%Molybdenum content: None.Typical max Hardness: 600 HB (After heat treatment).Typical Tensile Strength: 120 [Kpsi].Popular materilas: SAE 420 / 440.Typical parts: Razor blades, Surgical instruments, and other parts that require higher strength but are less critical in terms of corrosion resistance.Ferritic Stainless SteelFerritic stainless steel materials have a Chromium content of up to 18% with almost no nickel. They have better corrosion resistance than Martensitic grades but less than Austenitic ones. It cannot be hardened by heat treatments.Main Features of Ferritic Stainless Steel:Corrosion Resistance: Good – Moderate.Heat Treatable: No.Magnetic: YesChromium content: 11-18%Nickel content: 0-1%Molybdenum content: 0-1.25%.Typical max Hardness: 200 HB.Typical Tensile Strength: 100 [Kpsi].Popular grades: 409 / 430.Typical parts: Auto exhausts, grills, coffee machine parts, and other household appliances.Machinability of Ferritic/Martensitic Stainless-Steel 400 seriesMartensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

“In any hard part turning operation you are presenting a very negative cutting edge to the workpiece, which requires much better stability in all aspects than a typical turning operation,” said Andrews.

CBN tools have four properties that enable them to cut hard materials at high metal removal rates: high strength, high hardness, good thermal conductivity, and abrasion resistance.

Much like typical carbide inserts, there are different CBN grades available to choose from, depending on the application requirements.

Grinding is especially expensive if a custom wheel has to be made to handle a complex part’s geometry. Also, multiple setups often have to be done on the same grinding machine, all of which takes time. Hard part turning is done on one machine, typically in one setup, with standard inserts.

Ferritic stainless steel materials have a Chromium content of up to 18% with almost no nickel. They have better corrosion resistance than Martensitic grades but less than Austenitic ones. It cannot be hardened by heat treatments.Main Features of Ferritic Stainless Steel:Corrosion Resistance: Good – Moderate.Heat Treatable: No.Magnetic: YesChromium content: 11-18%Nickel content: 0-1%Molybdenum content: 0-1.25%.Typical max Hardness: 200 HB.Typical Tensile Strength: 100 [Kpsi].Popular grades: 409 / 430.Typical parts: Auto exhausts, grills, coffee machine parts, and other household appliances.Machinability of Ferritic/Martensitic Stainless-Steel 400 seriesMartensitic/Ferritic Stainless is on the border between ISO P and ISO M materials. It can be machined with carbide grades for both Alloy steel and Stainless steel. Typical wear is usually flank and crater (Like in alloy steel), with an occasional build-up edge. Machinability is better when compared to Austenitic stainless and is in the range of alloy steels. Grades with the suffix F (Like 430F/420F) are freecut materials with higher Sulfur (S) content and less Molybdenum (Mo). This tweak increases the machinability but results in lower corrosion resistance. Grades with the suffix C (like 440C), have higher Carbon (C) content, which increases the strength and hardness after heat treatment.Cutting Speeds Recommendations for 400 SeriesSAEMachinabilityTurningMilling430F75%920 SFM280 mm/min460 SFM140 mm/min41054%660 SFM200 mm/min330 SFM100 mm/min44040%530 SFM160 mm/min260 SFM80 mm/minPH Series Stainless SteelMain Features of Precipitation-hardening Stainless:Corrosion resistance: Good.Heat Treatable: Yes.Magnetic: Yes.Chromium content: 14-17%Nickel content: 4-10%Molybdenum content: 1.5-2.5%Typical max Hardness: 400 HB (After heat treatment)Typical Tensile Strength: 200 [Kpsi]Popular materials: 17-4PH (AISI 630)Typical parts: Aerospace and Oil & Gas components.A group of stainless steel alloys with good corrosion resistance that can be heat treated to provide tensile strengths of up to 3 times more than 304/316 grades. The addition of copper, aluminum, and titanium enables to achieves precipitation hardening. They are used in the oil & gas and aerospace industries, where a combination of strength and corrosion resistance is critical. SAE 17-4PH (Din X5CrNiCuNb174 / AISI 630), is the most popular in this family, with 45% machinability in the annealed state (Similar to 304), but much lower after heat treatment.Designation convention: Cr-Ni PH, for example, 17-4 PH, has 17% chromium and 4% nickel. (See more examples in below chart)Precipitation-hardening stainless steels can be divided into 3 main groups:GroupAlloyCrNiMartensitic15-5 PH15%5%17-4 PH(Alloy 630)17%5%Austenitic - Martensitic15-7 PH15%7%17-7 PH17%7%Austenitic17-10PH17%10%Alloy A286, with 26% nickel content, is classified as a PH alloy by some sources. We classify it as a nickel-based superalloy.PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

It is the heat and pressure created during the turning of hard materials that make a crater behind the cutting edge of the insert. It often is overlooked because the crater usually wears to the point where the entire edge of the insert fails and drops away. This can make it appear as if the insert has chipped prematurely, when in fact crater wear has caused the failure.

According to Geisel, Iscar Tools recently expanded its line of CBN grades to allow manufacturers to more finely tune their selection to each individual job.

“Wipers create an extended contact area between the tool and the part. The distance between the peaks and valleys produced by the insert are wider, and therefore the surface quality is better,” said Andrews.

“I always stress to operators to check the insert often by using a microscope or eye loupe to make sure the wear patterns are what they think they are before changing to a different tool,” said Andrews.

PH stainless steel alloys are available in two conditions – annealed (condition A) or tempered (condition C). The annealed alloys have a hardness of 20-30 HRC and are relatively easy to machine. After machining, parts can be age-hardened to Rockwell 32-42 HRC. Tempered (condition C) are delivered with a hardness of up to 43 HRC alloys can be hardened to above 50 HRC. Pay attention to the condition and hardness when determining the cutting speed.Duplex Stainless SteelCorrosion resistance: Excellent++.Heat Treatable: No.Magnetic: No.Chromium content: 18-30.0%Nickel content: 4-7%Molybdenum content: 0-5%Typical max Hardness: 280 HBTypical Tensile Strength: 150 [Kpsi]Popular materials: F51 (2205) and A276 (2707).Typical parts: Paper production equipment, Desalination of seawater, and Oil & Gas parts.This sub-group is called duplex since these materials have a two-phase Austenitic-Ferritic structure. They benefit from the advantages of both austenitic and ferritic properties, leading to increased strength, higher toughness, and broader corrosion resistance. They provide higher corrosion resistance and tensile strength than standard austenitic stainless 304 or 316. Chromium (Cr) content can reach 30% (Much higher than austenitic alloys) and Nickel (Ni) 9% (Lower than austenitic alloys). General machining guidelines are like 316, with about 20% lower machinability and more attention to clamping stability. Commercially, they are cheaper than austenitic stainless steels due to their lower nickel content. Duplex alloys lose their strength and corrosion resistance at temperatures above 570°F (300°C), limiting their application range!Duplex alloys are divided into two main categories:Alloys that are designed for highly corrosive environments but with less focus on their strength are nicknamed “lean” or “standard”.Alloys designed for Increased strength and mildly corrosive environments are nicknamed “Super-Duplex” or “Hyper-Duplex”.These categories are identified by the pitting resistance equivalence number (PREn), calculated based on the chemical composition:\( \large PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)\( \small PERn\,=\,\text{%Cr}\,+\,3.3\,\times\,\text{%Mo}\,+\,16\,\times\,\text{%N} \)Lean: PERn Less than 32Standard: PERn between 32-39Supper-Duplex: PERn between 40-45Hyper-Duplex: PERn Above 45Main Stainless Steel Duplex AlloysMaterialPERnCategoryMachinabilityCrDescriptionDuplex 1803 (F51)34Stabdard28%22%The original 22% Cr duplex stainless steel alloy.Duplex 2205(F60 / F51)36Stabdard28%22.5%An improved version of F51 (improved pitting corrosion resistance). Dual-certified as F60/F51 (S31803/S32205).Duplex 2760 (F55)43Supper-Duplex16%25%A super duplex stainless steel based upon a 25% Cr composition, but with an addition of tungsten.Duplex 2707 (A276)47Hyper-Duplex10%29%Extremely high mechanical strength and high resistance to stress corrosion cracking in chloride environments.Machinability TableThe below table lists the machinability ratings of all the major stainless steel alloys.Filter Material Groups:group_numpmkmr_group_nameMaterialMachinabilityBHNSAEDINWNR12MFerritic Stainless Steel40355%0403X7Cr131.400012MFerritic Stainless Steel40560%0405X10CrAl131.472412MFerritic Stainless Steel41055%0410X10Cr131.400612MFerritic Stainless Steel41690%041600X12CrS131.400512MFerritic Stainless Steel43054%0430X8Cr171.401612MFerritic Stainless Steel430F65%0430FX12CrMoS171.410412MFerritic Stainless Steel440A48%0440AX70CrMo151.410912MFerritic Stainless Steel44636%0446X10CrAl241.476212MFerritic Stainless SteelAermet 10032%0AMS 653213MMartensitic Stainless Steel42045%245420X20Cr131.402113MMartensitic Stainless Steel420F55%245420FX30Cr131.402813MMartensitic Stainless Steel43148%220431X22CrNi171.405713MMartensitic Stainless Steel440C35%285440CX105CrMo171.412514MAustenitic Stainless Steel30152%0301X12CrNi17-71.431014MAustenitic Stainless Steel30247%0302X12CrNi18-91.431914MAustenitic Stainless Steel30372%0303X8CrNiS18-91.430514MAustenitic Stainless Steel30443%0304X5CrNi18-91.435014MAustenitic Stainless Steel31640%0316X5CrNiMo17-13-31.440114MAustenitic Stainless Steel31738%0317X5CrNiMo17-131.444914MAustenitic Stainless Steel34736%0347X10CrNiNb18-91.455014MAustenitic Stainless SteelCustom 46530%0AMS 593660MDuplex Stainless SteelDuplex 1803 (F51)28%0ASTM A182 Grade F5160MDuplex Stainless SteelDuplex 2205 (F60 / F51)28%0ASTM A182 Grade F60X2CrNiMoN22-5-31.446260MDuplex Stainless SteelDuplex 2760 (F55)16%0ASTM A182 Grade F55X2CrNiMoCuWN25-7-41.450160MDuplex Stainless SteelHyper Duplex 2707 (A276)10%0A276X2CrNiMoCoN28-8-5-11.465865MPrecipitation Hardening St. St.15-5PH47%26015-5X4CrNiCuNb16.41.454065MPrecipitation Hardening St. St.17-4PH43%260630X5CrNiCuNb16-41.454265MPrecipitation Hardening St. St.32136%260321X10CrNiTi18-91.4541Related Glossary Terms:Nickel (Ni)HardnessCarbon (c)DuctilityBuilt-Up Edge (Bue)Molybdenum (MoBrinell scaleCutting EdgeNotch Wear (Vg)PVD (Physical Vapor Deposition)CVD (Chemical Vapor Deposition)Stainless SteelTurningMillingSteelGradeAlloy SteelFree-Machining SteelTitanium (Ti)SuperalloysRockwell scaleCutting SpeedToughnessChromium (Cr)Application Range

Hard part turning—turning a part that is harder than 45 Rockwell hardness C (HRC)—is gaining traction in many Canadian shops.

Many manufacturers will use high-pressure coolant not necessarily to extend tool life, but to aid in chip removal and improve process security. Warm parts and cold parts obviously will be different sizes because of thermal expansion. The use of high-pressure coolant can create thermal stability, keeping the part at a constant temperature.

“Parts such as landing gear can be on a machine for hours, and without coolant the part can expand to the point that the needed tolerances can no longer be met,” said Andrews. “At this point it’s more about component security than it is about extending tool life or chip removal.”

The best use of CBN cutting tools occurs in situations that cause carbide and ceramic tools to wear quickly or fail entirely.