| Cubic boron nitride has a number of attractive physical and chemical properties, such as low density, high thermal conductivity, and very high hardness comparable only to that of the diamond. Thermal stability and chemical stability of the c-BN is better than that of the diamond. c-BN is resistant to oxidation even heated to the 1000℃at the atmosphere, especially that it does not react with molten ferrous materials while diamond will be reacted. c-BN is very suitable for processing materials with high hardenss and great tenacity, such as harden quenching steel, high speed tools steel, bearing steel, titanium alloy, and so on. It is comprehensively applied in the field of auto manufacture, mechanical processing, precision processing, stone material processing, constructional materials, aviation, new material processing, and so on. c-BN is used to produce vary tools or superabrasive coats to persevere outside abrasion.The range and field of application of c-BN is restricted due to the bad processing property of c-BN superhard material. As an abrasive material, which is used to manufacture vary tools or superabrasive coats, the processing of c-BN is mainly produced by means of PVD, CVD, resin bond, vitrified bond, metal bond and electroplating, et al. The efficiency of c-BN produces prepared by using PVD, CVD processing is low. When the c-BN is prepared to be a coat or a wearable component by means of sinter processing, c-BN will be knocked down which was operated as the function of wearability. The lifespan of c-BN coat with electroplated processing is short, and it will contaminate the environment in processing. c-BN superhard material exhibits a stable electron figuration, it's hard to be wetted by melting metal. Hence, it's difficult to be bonded with other metal in normal welding material and normal wlding method. With the development of the welding material, the bond between c-BN and metal become the attractive...
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