Hassan A, Arif M, Shariq M (2019) Use of geopolymer concrete for a cleaner and sustainable environment—a review of mechanical properties and microstructure. J Clean Prod 223:704–728. https://doi.org/10.1016/j.jclepro.2019.03.051

Bernal SA, Rodriguez ED, de Gutierrez RM, Provis JL (2012) Performance of alkali-activated slag mortars exposed to acids. J Adv Cem Based Mater 1(3):138–151. https://doi.org/10.1080/21650373.2012.747235

Oderji SY, Chen B, Ahmad MR, Shah SFA (2009) Fresh and hardened properties of one-part fly ash-based geopolymer binders cured at room temperature: effect of slag and alkali activators. J Clean Prod 225:1–10. https://doi.org/10.1016/j.jclepro.2019.03.290

Tip Styles: The cutting tip of a flat bottom boring drill consists of one or more flat blades extending from the center to the outer edge. Flat bottom boring bits are available with or without spurs (teeth) at the outer diameter of the bit. Bits with spurs on the outer edge prevent chipping and splintering on wood or laminated surfaces. Some flat bottom boring bits also include a center spur to keep the bit from walking during the initial cut - Spade bits are a good example.

European Norm EN 15167-1: Ground granulated blast furnace slag for use in concrete, mortar and grout-Part 1: definitions, specifications and conformity criteria, Czech Office for Standards, Metrology and Testing, Czech Republic, 2006

Temuujin J, Williams RP, Van Riessen A (2009) Effect of mechanical activation of fly ash on the properties of geopolymer cured at ambient temperature. J Mater Process Technol 209(12–13):5276–5280. https://doi.org/10.1016/j.jmatprotec.2009.03.016

European Norm EN 196-1: Methods of testing cement. Part 1: determination of strength, Czech Office for Standards, Metrology and Testing, Czech Republic, 2016

Krivenko P (2017) Why alkaline activation—60 years of the theory and practice of alkali-activated materials. J Ceram Sci Technol 8(3):323–334. https://doi.org/10.4416/JCST2017-00042

Hitesh, Wattal R, Surabhi L (2021) Development and characterization of coal fly ash through low-energy ball milling. Mater Today Proc 47(11):2970–2975. https://doi.org/10.1016/j.matpr.2021.05.204

Kumar S, Kumar R, Bandopadhyay A, Alex TC, Kumar BR, Das SK, Mehrotra SP (2008) Mechanical activation of granulated blast furnace slag and its effect on the properties and structure of portland slag cement. Cem Concr Compos 30:679–685. https://doi.org/10.1016/j.cemconcomp.2008.05.005

Vlček J, Švrčinová R, Burda J, Topinková M, Klárová M, Ovčačíková H, Jančar D, Velička M (2016) Hydraulic properties of ladle slag. Metalurgija 55(3):399–402

Fernández-Jiménez A, Garcia-Lodeiro I, Maltseva O, Palomo A (2019) Mechanical-chemical activation of coal fly ashes: an effective way for recycling and make cementitious materials. Front Mater 6:51. https://doi.org/10.3389/fmats.2019.00051

Alrefaei Y, Wang YS, Dai JG (2021) Effect of mixing method on the performance of alkali-activated fly ash/slag pastes along with polycarboxylate admixture. Cem Concr Compos 117:103917. https://doi.org/10.1016/j.cemconcomp.2020.103917

Felekoğlu B, Türkel S, Kalyoncu H (2009) Optimization of fineness to maximize the strength activity of high-calcium ground fly ash—Portland cement composites. Constr Build Mater 23:2053–2061. https://doi.org/10.1016/j.conbuildmat.2008.08.024

Bakharev T, Sanjayana JG, Chengb YB (2002) Sulfate attack on alkali-activated slag concrete. Cem Concr Res 32:211–216. https://doi.org/10.1016/S0008-8846(01)00659-7

Ononiwu NH, Ozoegwu CG, Akinribide OJ, Akinlabi ET (2021) Effect of particle size on the microstructure and distribution of fly ash for metal matrix composite applications. Mater Today Proc 44(1):1118–1123. https://doi.org/10.1016/j.matpr.2020.11.227

*Note that most standard drill bits can be used in automated machinery (with the proper adapter) and most boring machine bits can be used in a portable drill or drill press (assuming the chuck is big enough). We have only organized them in this fashion to make selection easier.

Kumar R, Kumar S, Mehrotra SP (2007) Towards sustainable solutions for fly ash through mechanical activation. Resour Conserv Recycl 52:157–159. https://doi.org/10.1016/j.resconrec.2007.06.007

European Norm EN 196-6: Methods of testing cement—Part 6: determination of fineness, Czech Office for Standards, Metrology and Testing, Czech Republic, 2019

Vargas AS, Molin DC, Vilelac ACF, da Silva FJ, Pavão B, Veit H (2011) The effects of Na2O/SiO2 molar ratio, curing temperature and age on compressive strength, morphology and microstructure of alkali-activated fly ash-based geopolymers. Cem Concr Compos 33(6):653–660. https://doi.org/10.1016/j.cemconcomp.2011.03.006

Komljenović M, Baščarević Z, Bradić V (2010) Mechanical and microstructural properties of alkali-activated fly ash geopolymers. J Hazard Mater 181(1–3):35–42. https://doi.org/10.1016/j.jhazmat.2010.04.064

Institute of Environmental Technology, CEET, Nanotechnology Centre, CEET, VSB-Technical University of Ostrava, 17. Listopadu 2172/15, 708 00, Ostrava, Czech Republic

Hany E, Fouad N, Abdel-Wahab M, Sadek E (2020) Compressive strength of mortars incorporating alkali-activated materials as partial or full replacement of cement. Constr Build Mater 261:120518. https://doi.org/10.1016/j.conbuildmat.2020.120518

Hossain MM, Karim MR, Hossain MK, Islam MN, Zain MFM (2015) Durability of mortar and concrete containing alkali-activated binder with pozzolans: a review. Constr Build Mater 93:95–109. https://doi.org/10.1016/j.conbuildmat.2015.05.094

Puligilla S, Mondal P (2013) Role of slag in microstructural development and hardening of fly ash-slag geopolymer. Cem Concr Res 43:70–80. https://doi.org/10.1016/j.cemconres.2012.10.004

Flute Styles: Large flat bottom boring bits do not have flutes, they consist of only the cutting surface and the chips remain in the hole until the bit is removed.

Tip Styles: The cutting tip of a counterbore drill consists of one or more flat blades extending from the center drill to the outer edge. Counterbores are available with or without spurs (teeth) at the outer diameter of the bit. Counterbores with spurs on the outer edge prevent chipping and splintering on wood or laminated surfaces.

General Description: Specialty drill bits are any bit that doesn't fall into one of the four categories above. These bits include:

Chu YS, Davaabal B, Kim DS, Seo SK, Kim Y, Ruescher C, Temuujin J (2019) Reactivity of fly ashes milled in different milling devices. Rev Adv Mater Sci 58:179–188. https://doi.org/10.1515/rams-2019-0028

Kumar S, Kumar R, Mehrotra SP (2010) Influence of granulated blast furnace slag on the reaction, structure and properties of fly ash based geopolymer. J Mater Sci 45(3):607–615. https://doi.org/10.1007/s10853-009-3934-5

Puertas F, de Gutiérrez R, Fernández-Jiménez A, Delvasto S, Maldonado J (2002) Alkaline cement mortars. Chemical resistance to sulfate and seawater attack. Mater Constr 52(267):55–71. https://doi.org/10.3989/mc.2002.v52.i267.326

This work was supported by Ministry of Education, Youth and Sports of the Czech Republic via the “Institute of Environmental Technology—Excellent Research” project [Grant Number CZ.02.1.01/0.0/0.0/16_019/0000853]; the “Research on the management of waste, materials and other products of metallurgy and related sectors” project [Grant Number CZ.02.1.01/0.0/0.0/17_049/0008426]; and the SGS projects [Grant Numbers SP2022/13 and SP2022/68].

Kanti P, Sharma KV, Ramachandra CG, Minea AA (2020) Effect of ball milling on the thermal conductivity and viscosity of Indian coal fly ash nanofluid. Heat Transf 49(8):4475–4490. https://doi.org/10.1002/htj.21836

Pangdaeng S, Phoo-ngernkham T, Sata V, Chindaprasirt P (2014) Influence of curing conditions on properties of high calcium fly ash geopolymer containing Portland cement as additive. Mater Des 53:269–274. https://doi.org/10.1016/j.matdes.2013.07.018

Angulo-Ramírez DE, Valencia-Saavedra WG, Mejía de Gutiérrez R (2020) Alkali-activated concretes based on fly ash and blast furnace slag: Compressive strength, water absorption and chloride permeability. Ingeniería e Investigación 40(2):72–80. https://doi.org/10.15446/ing.investig.v40n2.83893

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European Norm EN 1927-5: Monolithic (unshaped) refractory products—Part 5: preparation and treatment of the test pieces, Czech Office for Standards, Metrology and Testing, Czech Republic, 2013

Guo X, Shi H, Dick WA (2010) Compressive strength and microstructural characteristics of class C fly ash geopolymer. Cem Concr Compos 32(2):142–147. https://doi.org/10.1016/j.cemconcomp.2009.11.003

Palomo A, Krivenko PV, Garcia-Lodeiro L, Kavalerova E, Maltseva O, Fernández-Jiménez A (2014) A review on alkaline activation: new analytical perspectives. Mater Construct. https://doi.org/10.3989/mc.2014.00314

Fernández-Jiménez A, Palomo A, Criado M (2005) Microstructure development of alkali-activated fly ash cement: a descriptive model. Cem Concr Res 35(6):1204–1209. https://doi.org/10.3989/mc.2006.v56.i281.92

Shank Styles: Countersinks for use in hand-held drills typically clamp on to a standard twist drill and therefore have a straight shank the same diameter as the center drill (some have 1/4" hex shanks for hand use in a bit holding screwdriver). Countersinks for use in automated machinery have fixed diameter (usually 1/2" or 10mm) shanks, threaded shanks, or specialty shanks designed for certain types of machines.

Ismail I, Bernal AS, Provis JL, Nicolas SR, Hamdan S, Van Deventer JSJ (2014) Modification of phase evolution in alkali-activated blast furnace slag by the incorporation of fly ash. Cem Concr Compos 45:125–135. https://doi.org/10.1016/j.cemconcomp.2013.09.006

Flute Styles: Some countersinks do not have flutes (except for the center drill) and simply shave away the material, others are designed similar to a twist drill with a replaceable center drill.

General Description: Flat bottom boring bits are similar to counterbores but do not include a center drill. These bits are designed to drill flat bottom blind holes for European style hinges, etc. Flat bottom boring bits are also used for drilling large diameter thru-holes without the plug that is typical when using a hole saw. These thru-hole bits are used for locks, door knobs, wiring holes, etc. Flat bottom boring bits on our site are designed for use in wood or plastics and are not intended for use in steel.

ASTM C618-19, Standard specification for coal fly ash and raw or calcined natural pozzolan for use in concrete, ASTM International, West Conshohocken, PA, (2019)

White SC, Case ED (1990) Characterization of fly ash from coal-fired power plants. J Mater Sci 25:5215–5219. https://doi.org/10.1007/BF00580153

MassMill wow

Blanco F, Garcia MP, Ayla J, Mayoral G, Garcia MA (2006) The effect of mechanical and chemical activated fly ashes on mortar properties. Fuel 85:2018–2026. https://doi.org/10.1016/j.fuel.2006.03.031

Wang A, Zheng Y, Zhang Z, Liu K, Li Y, Shi L, Sun D (2020) The durability of alkali-activated materials in comparison with ordinary Portland cements and concretes: a review. Engineering 6(6):695–706. https://doi.org/10.1016/j.eng.2019.08.019

Flute Styles: Most twist drills have flutes to evacuate the chips at an unspecified angle, and are suitable for the majority of applications. Some specialty twist drills may be designated as "High Helix", "Fast Spiral" or "Low Helix", "Slow Spiral" for specific applications requiring higher or lower spindle speeds or feed rates.

Kubba Z, Huseien GF, Sam ARM, Shah KW, Asaad MA, Ismail M, Tahir MM, Mirza J (2018) Impact of curing temperatures and alkaline activators on compressive strengthand porosity of ternary blended geopolymer mortars. Case Stud Constr Mater 9:e00205. https://doi.org/10.1016/j.cscm.2018.e00205

Fly ash and granulated blast-furnace slag can be considered "multifunctional waste." This study is focused on properties of a non-cement binder prepared from slag and fly ash activated by solid alkali activator. Fly ash was milled (2.5, 5.0, and 7.5 min) in order to increase its reactivity, and particle size distribution, specific surface area, and grain morphology were determined for all milled FA samples. Two GBFS + FA mixtures (70:30 and 85:15 w/w) were studied. Prepared mixtures were activated by solid alkali activator (Na2SiO3). Optimal weight ratios were calculated for CaO, SiO2, and Al2O3 components. Properties of the mixtures were studied in dependence on the GBFS:FA mass ratio and FA milling time (0–7.5 min). After 2 and 28 days of hydration, compressive strength of all mixtures exceeded 20 and 60 MPa, respectively. The 85:15 ratio led to generally higher compressive strength 108.3 MPa was reached after 90 days using FA milled for 7.5 min. Corrosion resistance was tested by exposing mixtures to distilled water, 0.5% HCl, and 3% Na2SO4 for 65 days, and evaluated by measuring changes in CS. Also the corrosion resistance was found higher (Na2SO4) than and comparable (HCl, water) to the 70:30 ratio. This study aims to show that GBFS + FA mixtures (70:30 and 85:15 w/w) activated by solid Na2SiO3 can achieve high CS and good corrosion resistance.

Millingmacro wotlk

Shank Styles: Twist drill bits designed for use in automated machinery have fixed diameter (usually 1/2" or 10mm) shanks, threaded shanks, or specialty shanks designed for certain machines. General purpose twist drills for use in portable drills have shanks the same diameter as the bit size (up to a certain diameter), larger diameter bits incorporate a reduced shank (either 1/4", 3/8" or 1/2") to fit into a standard drill chuck. Some bits have 3 flats on the shank to prevent spinning under high torque loads. Others have 1/4" hex shanks for use in a portable drill with a hex bit holder.

Centre for Advanced Innovation Technology, VSB-Technical University of Ostrava, 17. Listopadu 2172/15, 708 00, Ostrava, Czech Republic

With dozens of drill bit types and thousands of sizes to choose from we'll explain the differences and help you choose the right drill bit for your application.

Paul KT, Satpathy SK, Manna I, Chakraborty KK, Nando GB (2007) Preparation and characterization of nanostructured materials from fly ash: a waste from thermal power stations, by high energy ball milling. Nanoscale Res Lett 2:397–404. https://doi.org/10.1007/s11671-007-9074-4

Rodríguez E, Bernal S, de Gutiérrez RM, Puertas F (2008) Alternative concrete based on alkali-activated slag. Mater Constr 58(291):53–67. https://doi.org/10.3989/mc.2008.v58.i291.104

Coatings: General purpose drill bits are available with black oxide, bronze oxide, a combination of black and bronze oxide, and TiN coatings. Twist drills for automated machinery on our site are primarily for use in wood or plastics and are not coated.

Materials: General purpose twist drills for use in portable drills are available in different grades of high speed steel as well as cobalt steel and solid carbide. Twist drill bits for automated machinery are available in carbon steel, high speed steel, carbide tipped, and solid carbide.

Ovčačíková, H., Tokarský, J., Maierová, P. et al. Effect of Mass Ratio and Milling on Compressive Strength and Corrosion Resistance of Blast-Furnace Slag/Fly Ash Geopolymer Activated by Solid Alkali Activator. J. Sustain. Metall. 8, 1961–1974 (2022). https://doi.org/10.1007/s40831-022-00618-5

Yazdi MA, Liebscher M, Hempel S, Yang J, Mechtcherine V (2018) Correlation of microstructural and mechanical properties of geopolymers produced from fly ash and slag at room temperature. Constr Build Mater 191:330–341. https://doi.org/10.1016/j.conbuildmat.2018.10.037

Fernández-Jiménez A, Palomo A (2003) Characterisation of fly ashes. Potential React Alkaline Cem Fuel 82(18):2259–2265. https://doi.org/10.1016/S0016-2361(03)00194-7

Size Designations: Common twist drills for use in portable drills, etc. are available in fractional inch, wire sizes, letter sizes, and metric decimal millimeter. Twist drills for use in automated machinery are only available in fractional inch and decimal millimeter. See our Drill Bit Size Chart for the breakdown of fractional, letter, and wire sizes.

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Chaparro WA, Ruiz JHB, de Jesús Torres Gómez R (2012) Corrosion of reinforcing bars embedded in alkali-activated slag concrete subjected to chloride attack. Mater Res 15(1):57–62. https://doi.org/10.1590/S1516-14392011005000096

Shank Styles: Counterbores for use in hand-held drills typically clamp on to a standard twist drill and therefore have a straight shank the same diameter as the center drill. Counterbores for use in automated machinery have fixed diameter (usually 1/2" or 10mm) shanks, threaded shanks, or specialty shanks designed for certain machines.

Li H, Chen Y, Cao Y, Liu G, Li B (2015) Comparative study on the characteristics of ball-milled coal fly ash. J Therm Anal Calorim 124:839–846. https://doi.org/10.1007/s10973-015-5160-5

Chindaprasirt P, Jaturapitakkul C, Sinsiri T (2005) Effect of fly ash fineness on compressive strength and pore size of blended cement paste. Cem Concr Compos 27:425–428. https://doi.org/10.1016/j.cemconcomp.2004.07.003

Huseien GF, Tahir MM, Mirza J, Ismail M, Shah KW, Asaad MA (2018) Effects of POFA replaced with FA on durability properties of GBFS included alkali activated mortars. Constr Build Mater 175:174–186. https://doi.org/10.1016/j.conbuildmat.2018.04.166

Luukkonen T, Abdollahnejad Z, Yliniemi Y, Kinnunen P, Illikainen M (2014) One-part alkali-activated materials: a review. Cem Concr Res 103:21–34. https://doi.org/10.1016/j.cemconres.2017.10.001

Flute Styles: Some counterbores do not have flutes (except for the center drill) and simply shave away the material, others are designed similar to a twist drill with no tip angle and a replaceable center drill.

General Description: Countersink drill bits create a tapered surface hole with a smaller center hole that penetrates through the material (some are available without a center drill for countersinking existing holes). The purpose of a countersink is to allow a tapered head fastener to sit flush with the surface of the material. Countersinks on our site are designed for use in wood or plastics and are not intended for counterboring steel.

Drill bits are generally classified as Twist Drill, Counterbore, Countersink, Flat Bottom Boring, and Specialty. On our web site we have divided these into two categories:

Zhang J, Shi C, Zhang Z, Ou Z (2017) Durability of alkali-activated materials in aggressive environments: a review on recent studies. Constr Build Mater 152:598–613. https://doi.org/10.1016/j.conbuildmat.2017.07.027

General Description: Counterbore drill bits create a flat bottom blind hole with a smaller diameter center hole that penetrates through the material. The purpose of a counterbore is usually to conceal the fastener head (by covering the hole) or provide a recess to prevent the fastener from protruding above the surface of the material being drilled. Counterbores on our site are designed for use in wood or plastics and are not intended for counterboring steel.

Department of Thermal Engineering, Faculty of Materials Science and Technology, Institute of Environmental Technology, CEET, VSB-Technical University of Ostrava, 17. Listopadu 2172/15, 708 00, Ostrava, Czech Republic

Luukkonen T, Abdollahnejad Z, Yliniemi J, Kinnunen P, Illikainen M (2018) Comparison of alkali and silica sources in one-part alkali-activated blast furnace slag mortar. J Clean Prod 187:171–179. https://doi.org/10.1016/j.jclepro.2018.03.202

Mass millingguide

Tang XY, Xiao J, Chen F (2006) Effect and research progress of acid deposition on concrete durability. Mater Rev 20(10):97–101. https://doi.org/10.1016/j.eng.2019.08.019

Yang B, Jang JG (2020) Environmentally benign production of one-part alkali-activated slag with calcined oyster shell as an activator. Constr Build Mater 257(2):119552. https://doi.org/10.1016/j.conbuildmat.2020.119552

Wang KT, Du LQ, Lv XS, He Y, Cui XM (2017) Preparation of drying powder inorganic polymer cement based on alkali-activated slag technology. Powder Technol 312:204–209. https://doi.org/10.1016/j.powtec.2017.02.036

Petrakis E, Karmali V, Bartzas G, Komnitsas K (2019) Grinding kinetics of slag and effect of final particle size on the compressive strength of alkali activated materials. Minerals 9(11):714. https://doi.org/10.3390/min9110714

Shank Styles: Most large flat bottom boring bits have a fixed size hexagonal shank. The hex shank prevents the bit from spinning in the chuck under excessive loads.

Length Designations: The length of a twist drill has much to do with its rigidity - a shorter bit will be stronger and less likely to wander or break but may not have the reach needed for all jobs. Twist drill bits for use in automated machinery have an actual length specification (e.g. 4-1/2") while most (not all) twist drills for use in portable drills are graduated length and use a name to specify the length range:

Chi M, Huang R (2013) Binding mechanism and properties of alkali-activated fly ash/slag mortars. Constr Build Mater 40:291–298. https://doi.org/10.1016/j.conbuildmat.2012.11.003

Rashad AM (2014) A comprehensive overview about the influence of different admixtures and additives on the properties of alkali-activated fly ash. Mater Des 53:1005–1025. https://doi.org/10.1016/j.matdes.2013.07.074

Kumar S, Bandopadhyay A, Rajinikanth V, Alex TC, Kumar R (2004) Improved processing of blended cement through mechanical activation. J Mater Sci 39:3449–3452. https://doi.org/10.1023/B:JMSC.0000026948.85440.cc

Pacheco-Torgal F, Castro-Gomes J, Jalali S (2008) Alkali-activated binders: a review: Part 1. Historical background, terminology, reaction mechanisms and hydration products. Constr Build Mater 22(7):1305–1314. https://doi.org/10.1016/j.conbuildmat.2007.10.015

Tip Styles: The cutting tip of a countersink drill consists of two or more flat blades extending from the center drill to the outer edge. Countersinks are made with angles from 60 to 120 degrees but those on our site are typically 82 or 90 degrees. For wood use many times the manufacturer does not specify the angle.

General Description: Twist drill bits are the most common type of drill bit and are used for everyday drilling in all types of material. They are also the most confusing due to the sheer number of size, tip, and material specifications.

Huseien GF, Mohd Sam AR, Alyousef R (2020) Texture, morphology and strength performance of self-compacting alkali-activated concrete: role of fly ash as GBFS replacement. Constr Build Mater 270:121368. https://doi.org/10.1016/j.conbuildmat.2020.121368

Duxson P, Provis JL (2008) Designing precursors for geopolymer cements. J Am Ceram Soc 91(12):3864–3869. https://doi.org/10.1111/j.1551-2916.2008.02787.x

Huseien GF, Mirza J, Ismail M, Hussin MW (2016) Influence of different curing temperatures and alkali activators on properties of GBFS geopolymer mortars containing fly ash and palm-oil fuel ash. Constr Build Mater 125:1229–1240. https://doi.org/10.1016/j.conbuildmat.2016.08.153

Komljenović M, Baščarević Z, Marjanović N, Miladinović Z, Petrović R (2015) The influence of fly ash characteristics and reaction conditions on strength and structure of geopolymers. Constr Build Mater 94:361–370. https://doi.org/10.1016/j.conbuildmat.2015.07.014

Hajimohammadi A, van Deventer JSJ (2017) Characterisation of one-part geopolymer binders made from fly ash. Waste Biomass Valoriz 8:225–233. https://doi.org/10.1007/s12649-016-9582-5