Patent ID: 7771847

Claim:
A cBN sintered body for high surface integrity machining, having a cBN component of not less than 87% and not more than 99% by volume % and a thermal conductivity of 100 W/m·K or more, and an outermost surface of the cBN sintered body being coated with a heat resistant film having a thickness of 0.5 to 12 μm and comprising a compound of at least one element selected from 4a, 5a, 6a group elements and Al, and at least one element selected from C, N and O, wherein said cBN sintered body has a B to N mole ratio of not less than 1.10 and not more than 1.17 in the cBN component constituting said cBN sintered body, and, further includes carbon and at least one selected from a Co compound, an Al compound, a W compound or an oxygen compound as a binder material.