Desirable Characteristics of Cutting Tool Material
General requirement for cutting tool can be easily defined. There is no single cutting tool comprises all these properties. It is very hard to find the material of cutting tools that meets all these requirements. Physical, chemical and mechanical properties of good cutting tools which are essential for high quality and economical production are listed below
- Hot hardness - Tool must be harder than the workpiece material. They should maintain its hardness and strength even at high operating temperature (tool-work interaction causes high-temperature field at cutting zone). Otherwise, the tool will break during the cutting process.
- High yield strength at operating temperature.
- High toughness and bending strength.
- Excellent conductivity, low thermal expansion for good dimensional stability.
- High thermal shock resistant and fatigue resistant - They must withstand rapidly alternating temperature cycle during the cutting process.
- Excellent wear resistant- Required an acceptable tool life before it is replaced.
- Chemically stable and inert - Less soluble in workspace material and cutting fluid, corrosion resistant, oxidation resistant. Minimum adhesion and tool chip diffusion.
- High impact strength - They must resist the impact force due to vibrations or any other interrupted cutting.