View source for Engineering:Cutting tool material

'''Cutting tool materials''' are [[Physics:Material|material]]s that are used to make [[Engineering:Cutting tool|cutting tool]]s which are used in [[Engineering:Machining|machining]] ([[Engineering:Drill bit|drill bit]]s, [[Engineering:Tool bit|tool bit]]s, [[Engineering:Milling cutter|milling cutter]]s, etc.) but not other cutting tools like knives or [[Engineering:Punching|punch]]es.
Cutting tool materials must be harder than the material of the workpiece, even at high temperatures during the process.

The following properties are required for cutting tool
:<ref>Fritz Klocke: ''Manufacturing Processes 1 - Cutting'', Springer, 2011, p. 95.</ref>
*[[Physics:Hardness|hardness]], [[Physics:Hot hardness|hot hardness]] and pressure resistance
*bending strength and [[Physics:Toughness|toughness]]
*inner bonding strength
*wear resistance
**oxidation resistance
**small propensity for [[Physics:Diffusion|diffusion]] and [[Chemistry:Adhesion|adhesion]]
**abrasion resistance
**edge strength

There is no material that shows all of these properties at the same time. Very hard materials, have lower toughness and break more easily. The following cutting tool materials are used:
*[[Engineering:Tool steel|Tool steel]]s. They are relatively cheap and tough. Their hardness is sufficient to machine other steels.
**Carbon tool steels. They lose their hardness at 200&nbsp;°C
**High speed steels. They lose their hardness at 600&nbsp;°C, and are widely used in machining. Due to their ability to retain hardness at higher temperature, higher cutting speeds are possible.
*[[Chemistry:Cemented carbide|cemented carbide]]s. Harder than tool steels, but less tough. Can be used up to 900&nbsp;°C. There are many sort of cemented carbides like ones made of [[Chemistry:Tungsten carbide|tungsten carbide]] and [[Chemistry:Cobalt|cobalt]] or [[Chemistry:Cermet|cermet]]s.
*cutting ceramic. They are even harder than cemented carbides but have lower toughness. [[Chemistry:Aluminium oxide|Aluminium oxide]] and [[Chemistry:Silicon nitride|silicon nitride]] are used. The latter has higher toughness, but can't be used for machining Steel, due to very high wear.
*"super hard materials":
**cubic boron nitride. It is nearly as hard as diamond.
**[[Chemistry:Diamond|diamond]]. The hardest known material, but can only be used up to 600&nbsp;°C and can't be used to machine steel.

== References ==
<references />

== Further reading ==
*Trent, Wright: Metal Cutting. Butterworth Heinemann, 2000, 4. edition, p.&nbsp;132-250.
*J. Paulo Davim: ''Machining - Fundamentals and Recent Advances'', Springer, 2008, p.&nbsp;37-48.
*Fritz Klocke: ''Manufacturing Processes 1 - Cutting'', Springer, 2011, p.&nbsp;95-196.
*Graham T. Smith: ''Cutting Tool Technology - Industrial Handbook'', Springer, 2008, p.&nbsp;1-32.

[[Category:Machining]]
[[Category:Cutting tools]]

{{Sourceattribution|Cutting tool material}}