| abstract |
(57) [Summary] [Structure] Containing 30 to 85% by volume of cubic boron nitride, the balance being silicon nitride, aluminum nitride, aluminum oxide, It is composed of a mixture or compound of silicon oxide. Further, cubic boron nitride is contained in an amount of 30 to 85% by volume, and the balance is made of a mixture or compound of silicon nitride, aluminum nitride and rare earth metal oxide. [Effect] Since a binder that does not react with BN is used, a boron compound is not generated, which improves toughness and can greatly improve performance in interrupted cutting and heavy cutting, for example. |