HIGH HARDNESS AND STRENGTH SINTERED BODY

摘要

A sintered body contains hard particles having high pressure type boron nitride particles covered by a coating layer and a binding material for integrating these hard particles. The coating layer contains as a starting material at least one of nitride and boride of Ti, Zr and Hf and solid-solution thereof and has an average thickness of 0.09 .mu.m to 2 .mu.m. The binding material contains as starting material 0.5% to 40% by weight of one or more of Al, elements belonging to iron group and nitride and boride thereof, less than 5% by weight of oxide of these elements, and the balance of one or more of nitride and boride of Ti, Zr, Hf and Ta and inevitable impurities. The proportion of the hard particles in the total weight of unsintered starting materials is from 10% to 99% by weight.