| 摘要 |
PROBLEM TO BE SOLVED: To obtain a cBN sintered compact excellent in fracture resistance by optimizing the crater resistance and strength. SOLUTION: This cBN sintered compact is a sintered compact obtained by sintering cBN grains with a bonding phase which is continuous when two- dimensionally viewed. The bonding phase contains one or more kinds selected from the group consisting of carbides, nitrides, carbonitrides and borides of groups 4a, 5a and 6a transition metals of the periodic table, nitrides, borides and oxides of Al, carbides, nitrides, carbonitrides and borides of at least one kind of Fe, Co and Ni and mutual solid solutions thereof. The average value of the thickness of the bonding phase is <=1.5 μm and the standard deviation thereof is <=0.9. The content of the cBN is 45-70% expressed in terms of vol.% and the average grain size of the cBN grains is >=2 and <=6 μm. |
