Patent ID: 10081577

Abstract:
A cBN sintered body has 40%-85% cBN by volume and 15% to 60% binder phase by volume. and inevitable impurities. The binder phase has an Al compound including Al and at least one element selected from N, O and B, and a Zr compound including Zr and at least one element selected from C, N, O and B. The Zr compound includes ZrO, or ZrO and ZrO2. In an X-ray diffraction, where a peak intensity of a (111) plane of the ZrO is I1, a peak intensity of a (101) plane of tetragonal ZrO2 is I2t and a peak intensity of a (111) plane of cubic ZrO2 is I2c, a ratio of the intensity of I1 to total intensities of I1, I2t and I2c is 0.6-1.0, and an average grain size of the Al compound is 80 nm-300 nm.