Diamond is the hardest material in the world,they are widely used in machine,metallurgy,oil,geology,building materials,electron,instrument and meter,national defence industry and frontiers of technology.

Cubic boron nitride(CBN) is the secondary to diamond. CBN possesses good thermal stability and chemical inertness relating to the metals of the ferric family. CBN can be manufactured into all kinds of bonded grinding wheels and electroplated tools. It can be used in processing various kinds of hard and tough steels such as high-speed steel,high-vanadium steel and bearing steel etc.