Hard Turning the implementation process, cutting power (especially the radial force is greater than the main cutting force), high temperature cutting tool life is short, which requires to be used as a tool in Hard Turning the heat resistance and wear resistance Better machine process system must also have sufficient rigidity.

Tool material and geometric parameters can be used as a tool Turning Hard materials CBN (cbn), ceramics and new carbide. cbn has high hardness and wear resistance, hardness greater than hrc55 for machining hardened steel workpiece. Ceramic tool material costs less than cbn, and has good chemical thermal stability, hardness and wear resistance, but not as good as cbn, for less than the hardness of hardened steel workpiece hrc50 ceramic knives more appropriate choice. China's ceramic tool technology have been more perfect, more reliable performance blade, made al2o3, ceramic blade, nearly 20 varieties. Flexural strength and new carbide coated carbide tool materials and toughness than cbn and ceramic materials to be high, prices are low, can be used for machining hardened steel hardness of workpiece hrc40 ~ 50. Blade shape and tool geometry parameters of rational choice or not, it is essential to give full play to cutting tools. For blades of various materials, the choice should be high strength, good thermal conditions blade shape and nose radius as large as possible. The main features of the tool geometry is to select a large negative rake angle or pre-grind negative chamfer.