With GC1130, the resistance against chipping has been greatly improved through the introduction of extra predictability and security into the production process. The clean, intact edge of GC1130 promotes high metal removal rates and elevated performance in both wet and dry machining. Furthermore, it is suitable for both roughing and finishing applications.

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One of the secrets behind the premium performance of GC1130 is its high chromium (Cr) content fine-grained substrate. The inherent characteristics of chromium additions in the cemented carbide help withstand edge-line chipping and cracks arising from difficult machining environments such as temperature and/or load variations, as well as vibrations.

The Zertivo production technology is designed to take PVD process control to a new level, resulting in improved adhesion between the substrate and the coating, along with optimised cutting edge integrity. Ultimately, the concept behind Zertivo is to ensure that each grade is produced under the right conditions, resulting in a higher quality product for secure machining.

A wide range of materials, including metals and alloys, ceramics, glasses, semiconductors, and composites, are manufactured to meet service requirements to a given geometry, accuracy, finish, and surface integrity. Metals and alloys in general are easier to machine because of their high fracture toughness, low hardness, non-directional bonding, low porosity, large strain to fracture, and high impact energy. On the other hand, non-metals such as ceramics, semiconductors, optical crystals, and many infrared (IR) optical materials are characterized by covalent or ionic bonding, limited slip systems for plastic deformation, high hardness, and low fracture toughness, making them more challenging to machine.

Production engineers are tasked with continually searching for solutions that help deliver improved performance from milling insert grades. The arrival of GC1130, the first Sandvik Coromant milling grade manufactured using Zertivo technology, signals an opportunity for machine shops to take large strides towards greater process control, productivity and profitability. The result is the ability to compete more effectively for new contracts and build a more robust and successful business.

Ideal for square shoulder end milling cutters, GC1130 is first introduced on the CoroMill 390 with inserts in sizes 07 and 11, although further extensions are planned to follow shortly. In fact, GC1130 will also soon be available in most CoroMill variants. CoroMill 390 is a versatile concept for machining varied component features and materials; the assortment includes many different types of tools and a wide selection of corner radii.

A South West-based engineering team is aiming to transform the large-format additive manufacturing sector with the launch of its latest product.

The μ-LAM technology directly heats and thermally softens the workpiece material, in the chip deformation and generation zone, increasing the material's ductility. Improved ductility that results from reduced material hardness allows for easier chip formation, decreased brittleness, and ultimately higher material removal rates-all leading to better tool performance and increased productivity that in turn translates into lower manufacturing costs.

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With a less-than-eight-month payback, the μ-LAM system is proving its worth for many IR optical materials and crystals, with productivity improvements up to 500%, machine efficiency increases up to 200%, and improved part quality. μ-LAM processes are also being developed for ultrahard materials such as silicon carbide (SiC), sapphire, spinel, glass, and some selected metals used in the optics and aerospace industries.

Hundreds of British manufacturing companies opened their doors in a UK-wide open house today as part of National Manufacturing Day, giving their local communities the chance to see the highly paid careers and jobs on offer in our exciting and diverse sector.

GC1130, the first milling PVD grade produced with Zertivo technology, is optimised for steel milling in all conditions. When developing this advanced new grade, the focus was on solving the issues of chipping, insert flaking and thermal cracks, working with both substrate and coating, to reach longer tool life and secure machining, even in unstable or demanding conditions.

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In a customer example involving slot milling, a subcontractor’s productivity was limited by its standard grade end mill cutter. However, when switching to a CoroMill 390 with size 07 inserts and the GC1130 grade, the increased productivity afforded by a 33% increase in cutting speed from 150 to 200m/minute, and a 50% gain in table feed from 600 to 900mm/minute. Ensured time in cut was reduced from 5.5 to 3.8 minutes and tool life was considerably improved. Moreover, the result was achieved at a 3mm depth of cut, compared with 2mm for the competitor tool.

The advantages of PVD tooling grades are well documented – particularly with tough materials, but there’s always room for improvement. In this article, PES discovers how Sandvik Coromant, through its new Zertivo technology, is taking PVD to the next level.

Thanks to intrinsic properties such as compressive residual stresses, and high hot hardness, PVD grades are a good choice when it comes to milling operations that demand toughness or sharp cutting edges to help overcome sticky materials.

Optical-grade Si is typically used as a lens for IR imaging systems. Previously, Ge was a favored material, as it is typically easier (softer) to machine. However, there are several advantages of Si over Ge, such as lighter weight, lower cost for the bulk material, and better thermal stability and mechanical properties-primarily higher hardness.

In addition to Si, the μ-LAM process also improves productivity for other crystals and IR materials (see Table 2). μ-LAM is also an enabling technology, producing high-quality, large-diameter Si optics and all sizes of CaF2 optics compared to zero acceptable parts using conventional diamond turning alone.

Although the increased hardness in Si is preferred to minimize part failure during service, it also makes it much more difficult to machine. The hardness and abrasiveness of Si causes the diamond tool to rapidly wear, yielding poor part quality and high form errors. The μ-LAM process has shown significant benefits in machining Si and other optical crystals, as it temporarily reduces the workpiece material's hardness, resulting in significantly less tool wear.

Recently, μ-LAM technology has made some groundbreaking progress in machining optical-quality tungsten carbide (WC) using a diamond-turning process. While favored in the glass molding industry, as it performs well under high temperature and high-pressure applications, WC is an extremely hard material (about 3X harder than Si) and, therefore, has never been successfully diamond-turned to an optical quality surface. The status-quo process to manufacture WC optical molds is to grind and polish them in an arduous 3–4 hour per-part process.

For our analysis, the μ-LAM system was mounted on a UPL to machine a diffractive Si lens (see Fig. 1). The μ-LAM system's tool post, termed Optimus T+1, is a bolt-on system that replaces the existing tool post and takes <60 min to retrofit. The laser controls are connected to the UPL, enabling it to be controlled with an M-code command.

Deepak Ravindra is CEO, Sai Kumar Kode is lead process engineer, and Chris Stroshine is global sales manager, all at Micro-LAM, Portage, MI; e-mail: [email protected]; www.micro-lam.com.

In effect, the R&D team at Sandvik Coromant has discovered the art of creating the ideal PVD grades, where carefully combined ingredients for both the coating and substrate are merged with precisely controlled process conditions to produce inserts with unbeatable edge line security.

The Optimus T+1 was coupled to a 1064 nm yttrium aluminum garnet (YAG) laser via a fiber-optic cable and collimated lens. The diamond tool is optically transparent to the wavelength of the laser and fabricated to perform as a focusing lens that directs the beam precisely to the tool's cutting edge radius. This allows for only the cutting zone of the material to be heated and softened.

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The challenges of milling ISO P materials are well documented. In the first instance, complex toolpaths or difficult to machine materials can cause edge line chipping that leads to poor surface finish and tool failure.

Several customer test sites are already demonstrating the potential gains on offer to discerning production engineers responsible for machine shops where investment and continuous improvement are priorities in a fiercely competitive marketplace.

Coalville, Leicestershire-based CMS Cepcor is a leading supplier of aftermarket crusher spares, manganese-steel wear liners and other equipment for the mining, aggregate production and associated industries worldwide.

When developing Zertivo, Sandvik Coromant focused on creating a platform that would make it possible to offer the perfect balance between various properties to match the requirements of the market. Here, the team deduced that developing a new grade is about optimizing the interplay of several properties, and this is where the company has attained new levels of success with Zertivo.

Creating a high quality PVD coating includes many complex process steps; the main ones being pumping, heating, etching, coating and cooling. Besides coating composition, process parameters such as temperature, gas flow and pressure are crucial for final tool performance. After all, variations in the production processes have direct impact on the grade and, ultimately, how the tool performs on the machine.

Milling steel in the ISO P materials classification is not without its challenges. Tricky tool paths and thermal fluctuations, in combination with tough or ‘sticky’ materials, means that production engineers have faced a long battle to optimise steel milling operations.

Compared to standard diamond turning, the μ-LAM process not only produces good Si part quality with more than 3X reduction in surface roughness, but it also enables increased manufacturing productivity, more than quadrupling the number of parts that can be produced in a single shift (see Table 1).

The advantages of PVD tooling grades are well documented – particularly with tough materials, but there’s always room for improvement. In this article, PES discovers how Sandvik Coromant, through its new Zertivo technology, is taking PVD to the next level. Milling steel in the ISO P materials classification is not without its challenges. Tricky tool paths and thermal fluctuations, in combination with tough or ‘sticky’ materials, means that production engineers have faced a long battle to optimise steel milling operations. In recent years, PVD (physical vapour deposition) grades have proven a popular choice, but even these can be compromised (depending on application) in terms of crack formation and/or edge line chipping. As a result, Sandvik Coromant has set about reinventing PVD grade technology from the ground up, creating GC1130, a purpose-designed steel milling grade that is the first to take advantage of Zertivo, a new method of production that results in benefits such as longer tool life and enhanced security. GC1130 insert size 07 The challenges of milling ISO P materials are well documented. In the first instance, complex toolpaths or difficult to machine materials can cause edge line chipping that leads to poor surface finish and tool failure. Indeed, milling some of the more ‘tacky’ materials in the ISO P classification can cause flaking of the insert coating, which in turn leads to breakage of the edge line. Furthermore, thermal fluctuations during machining, especially under wet conditions, can cause crack formation, an undesirable effect that tends to induce unpredictable tool life and even sudden breakage. For these reasons, correct insert grade selection is paramount to process security, productivity and profitability. Thanks to intrinsic properties such as compressive residual stresses, and high hot hardness, PVD grades are a good choice when it comes to milling operations that demand toughness or sharp cutting edges to help overcome sticky materials. Enhanced ISO P milling GC1130, the first milling PVD grade produced with Zertivo technology, is optimised for steel milling in all conditions. When developing this advanced new grade, the focus was on solving the issues of chipping, insert flaking and thermal cracks, working with both substrate and coating, to reach longer tool life and secure machining, even in unstable or demanding conditions. One of the secrets behind the premium performance of GC1130 is its high chromium (Cr) content fine-grained substrate. The inherent characteristics of chromium additions in the cemented carbide help withstand edge-line chipping and cracks arising from difficult machining environments such as temperature and/or load variations, as well as vibrations. To amplify the important potential advantages of using PVD grades, Sandvik Coromant has devised a new production technology called Zertivo, which takes the whole insert into consideration, not just the coating. Creating a high quality PVD coating includes many complex process steps; the main ones being pumping, heating, etching, coating and cooling. Besides coating composition, process parameters such as temperature, gas flow and pressure are crucial for final tool performance. After all, variations in the production processes have direct impact on the grade and, ultimately, how the tool performs on the machine. The Zertivo production technology is designed to take PVD process control to a new level, resulting in improved adhesion between the substrate and the coating, along with optimised cutting edge integrity. Ultimately, the concept behind Zertivo is to ensure that each grade is produced under the right conditions, resulting in a higher quality product for secure machining. The right balance When developing Zertivo, Sandvik Coromant focused on creating a platform that would make it possible to offer the perfect balance between various properties to match the requirements of the market. Here, the team deduced that developing a new grade is about optimizing the interplay of several properties, and this is where the company has attained new levels of success with Zertivo. In effect, the R&D team at Sandvik Coromant has discovered the art of creating the ideal PVD grades, where carefully combined ingredients for both the coating and substrate are merged with precisely controlled process conditions to produce inserts with unbeatable edge line security. With GC1130, the resistance against chipping has been greatly improved through the introduction of extra predictability and security into the production process. The clean, intact edge of GC1130 promotes high metal removal rates and elevated performance in both wet and dry machining. Furthermore, it is suitable for both roughing and finishing applications. Ideal for square shoulder end milling cutters, GC1130 is first introduced on the CoroMill 390 with inserts in sizes 07 and 11, although further extensions are planned to follow shortly. In fact, GC1130 will also soon be available in most CoroMill variants. CoroMill 390 is a versatile concept for machining varied component features and materials; the assortment includes many different types of tools and a wide selection of corner radii. CoroMill 390 with insert size 07 Several customer test sites are already demonstrating the potential gains on offer to discerning production engineers responsible for machine shops where investment and continuous improvement are priorities in a fiercely competitive marketplace. In a customer example involving slot milling, a subcontractor’s productivity was limited by its standard grade end mill cutter. However, when switching to a CoroMill 390 with size 07 inserts and the GC1130 grade, the increased productivity afforded by a 33% increase in cutting speed from 150 to 200m/minute, and a 50% gain in table feed from 600 to 900mm/minute. Ensured time in cut was reduced from 5.5 to 3.8 minutes and tool life was considerably improved. Moreover, the result was achieved at a 3mm depth of cut, compared with 2mm for the competitor tool. The future of PVD, today Production engineers are tasked with continually searching for solutions that help deliver improved performance from milling insert grades. The arrival of GC1130, the first Sandvik Coromant milling grade manufactured using Zertivo technology, signals an opportunity for machine shops to take large strides towards greater process control, productivity and profitability. The result is the ability to compete more effectively for new contracts and build a more robust and successful business. Sandvik Coromant www.sandvik.coromant.com/uk

To demonstrate extended tool life, many Si diffractive lenses were machined using the μ-LAM process and analyzed for surface roughness and form error using a white light interferometer with a standard Gaussian 0.08 mm filter applied. Note that the part numbers correspond to the order in which they were machined—for example, part 12 would be the 12th part the tool would have machined.

For a 17-mm-diameter WC part, machining time is 90 seconds. With a required Sa spec for this <5 nm part, the μ-LAM process yielded roughness values of 2 to 2.5 nm.

After optimizing such machining parameters as the depth of cut, cross feed, cutting speed, and laser power, several Si lenses were fabricated and evaluated for their surface finish (roughness), surface aesthetics (spokes, brittle bands), form accuracy or irregularity tolerance, tool life (based on the number of parts fabricated), and productivity (pushing the machining parameters to enhance production).

To evaluate the machinability of optical-grade crystals via the μ-LAM process, machining tests were performed on a diamond-turning ultra-precision lathe (UPL) with a 15 pm positional accuracy feedback system. Such UPLs are designed for producing optical lenses, optical mold inserts and mirrors, and small precision mechanical components.

In recent years, PVD (physical vapour deposition) grades have proven a popular choice, but even these can be compromised (depending on application) in terms of crack formation and/or edge line chipping. As a result, Sandvik Coromant has set about reinventing PVD grade technology from the ground up, creating GC1130, a purpose-designed steel milling grade that is the first to take advantage of Zertivo, a new method of production that results in benefits such as longer tool life and enhanced security.

A typical Si diffractive lens used in an IR optical system with a 50.4 mm diameter, for example, has a 0.5 fringe irregularity tolerance, surface roughness <10 nm Sa, 60-40 surface quality, no spokes, and no gray or brittle bands. The primary challenge here is achieving the 0.5 fringe (<160 nm) irregularity tolerance that can only be achieved with a well-preserved (not worn) cutting tool edge.

A new technology called micro-laser-assisted machining (μ-LAM) is gaining traction for machining optical crystals and IR materials including silicon (Si), calcium fluoride (CaF2), zinc selenide (ZnSe), germanium (Ge), and zinc sulfide (ZnS). As evidenced by a materials study undertaken at Micro-LAM, the value proposition for μ-LAM technology includes extended tool life, increased productivity, and improved part quality during the manufacture of optical crystals and IR optics.

To amplify the important potential advantages of using PVD grades, Sandvik Coromant has devised a new production technology called Zertivo, which takes the whole insert into consideration, not just the coating.

Indeed, milling some of the more ‘tacky’ materials in the ISO P classification can cause flaking of the insert coating, which in turn leads to breakage of the edge line. Furthermore, thermal fluctuations during machining, especially under wet conditions, can cause crack formation, an undesirable effect that tends to induce unpredictable tool life and even sudden breakage. For these reasons, correct insert grade selection is paramount to process security, productivity and profitability.