Cutting tool materials are materials that are used to make cutting tools which are used in

machining Machining is a process in which a material (often metal) is cut to a desired final shape and size by a controlled material-removal process. The processes that have this common theme are collectively called subtractive manufacturing, which utilizes ...

( drill bits,

tool bit A tool bit is a non-rotary cutting tool used in metal lathes, shapers, and planers. Such cutters are also often referred to by the set-phrase name of single-point cutting tool, as distinguished from other cutting tools such as a saw or water jet ...

s, milling cutters, etc.) but not other cutting tools like knives or

punch Punch commonly refers to: * Punch (combat), a strike made using the hand closed into a fist * Punch (drink), a wide assortment of drinks, non-alcoholic or alcoholic, generally containing fruit or fruit juice Punch may also refer to: Places * Pun ...

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 :Fritz Klocke: ''Manufacturing Processes 1 - Cutting'', Springer, 2011, p. 95. * hardness,

hot hardness Hot or the acronym HOT may refer to: Food and drink *Pungency, in food, a spicy or hot quality *Hot, a wine tasting descriptor Places *Hot district, a district of Chiang Mai province, Thailand **Hot subdistrict, a sub-district of Hot District ...

and pressure resistance *

bending strength Flexural strength, also known as modulus of rupture, or bend strength, or transverse rupture strength is a material property, defined as the stress in a material just before it yields in a flexure test. The transverse bending test is most freque ...

and toughness *inner bonding strength * wear resistance ** oxidation resistance **small propensity for diffusion and 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: * Tool steels. They are relatively cheap and tough. Their hardness is sufficient to machine other steels. **Carbon tool steels. They lose their hardness at 200 °C ** High speed steels. They lose their hardness at 600 °C, and are widely used in machining. Due to their ability to retain hardness at higher temperature, higher cutting speeds are possible. *

cemented carbide Cemented carbides are a class of hard materials used extensively for cutting tools, as well as in other industrial applications. It consists of fine particles of carbide cemented into a composite by a binder metal. Cemented carbides commonly use ...

s. Harder than tool steels, but less tough. Can be used up to 900 °C. There are many sort of cemented carbides like ones made of tungsten carbide and cobalt or cermets. * cutting ceramic. They are even harder than cemented carbides but have lower toughness. Aluminium oxide and 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. ** diamond. The hardest known material, but can only be used up to 600 °C and can't be used to machine steel.

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Further reading