Cubic boron nitride (CBN) high hardness, good thermal conductivity, and difficult to react with iron materials, performance, second only to diamonds. Polycrystalline cubic boron nitride (PCBN) is the use of ceramic bonding agent on the sintering of CBN particles; PCBN contributed to the hardening of steel processing technology by the grinding innovation to cut. The PCBN cutting tool produced by Sumitomo Electric Hardmetal Company can significantly improve the production efficiency and reduce the cost in the finishing and semi-finishing process of ferrous materials such as cast iron. On the other hand, due to the high strength of PCBN, good thermal conductivity and applied to high-precision cast iron processing. For example, surface finishing of engine and oil pumps is usually done with a PCBN cutting tool. This paper mainly discusses the milling of cast iron with the new PCBN tool.

There are two types of PCBN sintered bodies: one is to bond the CBN particles to the binder; the other is to bond the CBN particles together with a small amount of binder material. The former good wear resistance, and hardened steel cutting; or CBN content of high thermal conductivity, for cast iron processing, heat-resistant alloys and PM components. BN7000 will be classified as the latter.