Abstract: A cubic boron nitride sintered body including cubic boron nitride and a binder phase, wherein: a content ratio of the cubic boron nitride is 85 volume % or more and 95 volume % or less, a content ratio of the binder phase is 5 volume % or more and 15 volume % or less, the binder phase contains Co3W3C, W2Co21B6, and an Al compound, and IB/IA is 0.02 or more and 0.15 or less, IC/IA is 0.02 or more and 1.00 or less, and IC?ID, where IA denotes an X-ray diffraction peak intensity of a (111) plane of the cubic boron nitride, IB denotes an X-ray diffraction peak intensity of a (400) plane of the Co3W3C, IC denotes an X-ray diffraction peak intensity of a (420) plane of the W2Co21B6, and ID denotes an X-ray diffraction peak intensity of a (001) plane of WC.

Abstract: A cubic boron nitride sintered body including cubic boron nitride and a binder phase, wherein: a content of the cubic boron nitride is 81 volume % or more and 95 volume % or less and a content of the binder phase is 5 volume % or more and 19 volume % or less based on the total amount of the sintered body; and a content of Al in the binder phase is 0.5 mass % or more and 5 mass % or less, a content of W in the binder phase is 2 mass % or more and 10 mass % or less, a content of V in the binder phase is 2 mass % or more and 8 mass % or less, and a content of Cr in the binder phase is 0 mass % or more and 5 mass % or less, based on 100 mass % in total of all elements contained in the sintered body.

Abstract: A coated cBN sintered body has excellent wear resistance, fracture resistance, adhesiveness between a substrate and a coating, and a tool life of which is elongated as compared with conventional cBN sintered bodies. The coated cBN sintered body has a cBN sintered body substrate and a coating coated on the surface thereof. The cBN sintered body includes 76 to 90% by volume of cBN, and 10 to 24% by volume of a binder phase and inevitable impurities. An average grain size of cBN is 0.5 to 5.0 ?m, an average value of the thickness of the binder phase is 0.05 to 0.8 ?m, and the standard deviation of the thickness of the binder phase is 0.8 ?m or less.

Abstract: A coated cBN sintered body has excellent wear resistance, fracture resistance, adhesiveness between a substrate and a coating, and a tool life of which is elongated as compared with conventional cBN sintered bodies. The coated cBN sintered body has a cBN sintered body substrate and a coating coated on the surface thereof. The cBN sintered body includes 76 to 90% by volume of cBN, and 10 to 24% by volume of a binder phase and inevitable impurities. An average grain size of cBN is 0.5 to 5.0 ?m, an average value of the thickness of the binder phase is 0.05 to 0.8 ?m, and the standard deviation of the thickness of the binder phase is 0.8 ?m or less.