Abstract: A cubic boron nitride sintered body includes cubic boron nitride, a binder, and a metal catalyst element, a content by percentage of the cubic boron nitride is 50 vol % or more and 85 vol % or less, a content by percentage of the catalyst is 0.5 mass % or more and 5 mass % or less. A sum of a detected peak value of nitrogen and a detected peak value of boron at each of arbitrary measurement points on line segments is calculated, a measurement point at which the sum is a half or less of a maximum value among the 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 the catalyst element is not detected among the binder-portion measurement points, to a total number of all binder-portion measurement points, is 30% or less.

Abstract: A surface-coated boron nitride sintered body tool is provided, in which at least a cutting edge portion includes a cubic boron nitride sintered body and a coating film formed on the cubic boron nitride sintered body. The coating film includes an A layer, a B layer and a C layer. The C layer is provided between the A layer and the B layer. The A layer contains Ti and the like. The B layer is formed by alternately stacking a B1 compound layer containing Ti, Si and the like and a B2 compound layer containing Al and the like. The C layer includes McLczc (Mc represents one or more of group 4 elements, group 5 elements and group 6 elements in a periodic table, Al and Si; Lc represents one or more of B, C, N, and O; and zc is 0.05 or more and 0.85 or less).

Abstract: A cubic boron nitride sintered body includes cubic boron nitride, a binder, and a metal catalyst element, a content by percentage of the cubic boron nitride is 50 vol % or more and 85 vol % or less, a content by percentage of the catalyst is 0.5 mass % or more and 5 mass % or less. A sum of a detected peak value of nitrogen and a detected peak value of boron at each of arbitrary measurement points on line segments is calculated, a measurement point at which the sum is a half or less of a maximum value among the 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 the catalyst element is not detected among the binder-portion measurement points, to a total number of all binder-portion measurement points, is 30% or less.