Patent ID: 9487449
Filing Date: 2016-11-08
CPC Classification: B22F,B28B,C04B,C22C,C23C

Claim Text:
1. A cubic boron nitride sintered body comprising cubic boron nitride, a binder, and a catalyst element of a metal, a content by percentage of said cubic boron nitride being 50 vol % or more and 85 vol % or less, a content by percentage of said catalyst element being 0.5 mass % or more and 5 mass % or less, and said binder including: at least one selected from the group consisting of nitrides, carbides, borides, and oxides of Group 4a elements, Group 5a elements, and Group 6a elements in the periodic table, and solid solutions thereof; and an aluminum compound, wherein an image obtained through observation of a region of 8 μm×8 μm of a structure of said cubic boron nitride sintered body with a scanning transmission electron microscope is divided along line segments into partial regions in four rows and four columns, a composition analysis is performed on the line segments, and a sum of a detected peak value of nitrogen and a detected peak value of boron at each of arbitrary measurement points on said line segments is calculated, a measurement point at which said sum is a half or less of a maximum value among said sums at all measurement points respectively is identified as a binder-portion measurement point, and a ratio of the number of measurement points at which said catalyst element is not detected among said binder-portion measurement points, to a total number of all said binder-portion measurement points is 30% or less, wherein said catalyst element includes at least one element selected from the group consisting of cobalt, chromium, nickel and molybdenum.