Abstract: A cubic boron nitride sintered material comprising cubic boron nitride grains, a binder phase, and a void, in which a percentage of the cubic boron nitride grains based on the total of the cubic boron nitride grains and the binder phase is 40 vol % to 70 vol %, a percentage of the binder phase based on the total of the cubic boron nitride grains and the binder phase is 30 vol % to 60 vol %, the binder phase includes 10 vol % to 100 vol % of aluminum oxide grains, an average grain size of the aluminum oxide grains is 50 to 250 nm, the cubic boron nitride sintered material comprises 0.001 vol % to 0.100 vol % of one or more first voids, and at least one portion of each of the first voids is in contact with the aluminum oxide grains.

Abstract: A cubic boron nitride sintered material comprising cubic boron nitride grains, a binder phase, and a void, in which a percentage of the cubic boron nitride grains based on the total of the cubic boron nitride grains and the binder phase is 40 vol % to 70 vol %, a percentage of the binder phase based on the total of the cubic boron nitride grains and the binder phase is 30 vol % to 60 vol %, the binder phase includes 10 vol % to 100 vol % of aluminum oxide grains, an average grain size of the aluminum oxide grains is 50 to 250 nm, the cubic boron nitride sintered material comprises 0.001 vol % to 0.100 vol % of one or more first voids, and at least one portion of each of the first voids is in contact with the aluminum oxide grains.

Abstract: A cubic boron nitride sintered material includes: to 98 volume % of cubic boron nitride grains; and a binder phase, wherein the binder phase includes at least one selected from a group consisting of one or more first compounds and a solid solution originated from the first compounds, the cubic boron nitride grains include, on number basis, more than or equal to 50% of cubic boron nitride grains each having an equivalent circle diameter of more than 0.5 ?m, and includes, on number basis, less than or equal to 50% of cubic boron nitride grains each having an equivalent circle diameter of more than 2 ?m, and when a mass of the cubic boron nitride grains is assumed as 100 mass %, a total content of lithium, magnesium, calcium, strontium, beryllium, and barium in the cubic boron nitride grains is less than 0.001 mass %.

Abstract: A cubic boron nitride sintered material includes: 0 to 85 volume % of cubic boron nitride grains; and a binder phase, wherein the binder phase includes at least one selected from a group consisting of one or more first compounds and a solid solution originated from the first compounds, the cubic boron nitride grains include, on number basis, more than or equal to 50% of cubic boron nitride grains each having an equivalent circle diameter of more than 0.5 ?m, and includes, on number basis, less than or equal to 50% of cubic boron nitride grains each having an equivalent circle diameter of more than 2 ?m, and when a mass of the cubic boron nitride grains is assumed as 100 mass %, a total content of lithium, magnesium, calcium, strontium, beryllium, and barium in the cubic boron nitride grains is less than 0.001 mass %.

Abstract: A diamond cutting tool comprises a base metal part and a diamond part joined to the base metal part, wherein the base metal part is made of an alloy containing tungsten carbide, the diamond part configures at least a cutting blade, the cutting blade comprises a portion of a rake face, a portion of a flank face, and a ridge line at which the rake face and the flank face cross, the diamond cutting tool has a region A, the region A is a region that is present bridging over the three, which are the rake face, the ridge line, and the flank face on the surface of the cutting blade, and the region A has a surface roughness Ra of not more than 0.2 ?m and a concentration of tungsten element of not more than 1 mass %.

Abstract: A drill includes a blade tip part that is formed of diamond and a trunk part that is formed of diamond and is continuous with the blade tip part, the drill rotating about a drill axis, the blade tip part includes N cutting edges where N is an integer of no less than 4, and a proportion of S1 to S2 is no less than 30% and no more than 60%, where S1 is an area of the drill in a cross-section with the drill axis as a normal line, the cross-section including a boundary between the blade tip part and the trunk part, r is a maximum value of a distance from the drill axis to an outer edge of the drill in the cross-section and S2 is an area of a circle with r as a radius.

Abstract: A cubic boron nitride sintered material includes 40% by volume or more and 96% by volume or less of cubic boron nitride grains and 4% by volume or more and 60% by volume or less of a binder phase, and the cubic boron nitride grains have a dislocation density of less than 1×105/m2.

Abstract: A polycrystalline cubic boron nitride comprising 96% by volume or more of cubic boron nitride, wherein the cubic boron nitride has a dislocation density of more than 8×1015/m2, the polycrystalline cubic boron nitride comprises a plurality of crystal grains, and the plurality of crystal grains have a median diameter d50 of an equivalent circle diameter of less than 100 nm.

Abstract: A polycrystalline cubic boron nitride comprising 98.5% by volume or more of cubic boron nitride, wherein the cubic boron nitride has a dislocation density of more than 8×1015/m2, the polycrystalline cubic boron nitride comprises a plurality of crystal grains, and the plurality of crystal grains have a median diameter d50 of an equivalent circle diameter of 0.1 ?m or more and 0.5 ?m or less.

Abstract: A polycrystalline cubic boron nitride comprising 96% by volume or more of cubic boron nitride, wherein the cubic boron nitride has a dislocation density of 8×1015/m2 or less, the polycrystalline cubic boron nitride comprises a plurality of crystal grains, and the plurality of crystal grains have a median diameter d50 of an equivalent circle diameter of less than 100 nm.

Abstract: A cubic boron nitride sintered material comprises 30% by volume or more and 80% by volume or less of cubic boron nitride grains and 20% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grains having a dislocation density of 3×1017/m2 or more and 1×1020/m2 or less.

Abstract: A cubic boron nitride sintered material comprises 30% by volume or more and 80% by volume or less of cubic boron nitride grains and 20% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grains having a dislocation density of 3×1017/m2 or more and 1×1020/m2 or less.

Abstract: The cubic boron nitride sintered material comprises 30% by volume or more and 80% by volume or less of cubic boron nitride grains and 20% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grains having a dislocation density of 1×1015/m2 or more and 1×1017/m2 or less.

Abstract: A polycrystalline cubic boron nitride comprising 98.5% by volume or more of cubic boron nitride, wherein the cubic boron nitride has a dislocation density of more than 8×1015/m2, the polycrystalline cubic boron nitride comprises a plurality of crystal grains, and the plurality of crystal grains have a median diameter d50 of an equivalent circle diameter of 0.1 ?m or more and 0.5 ?m or less.

Abstract: A polycrystalline cubic boron nitride comprising 96% by volume or more of cubic boron nitride, wherein the cubic boron nitride has a dislocation density of more than 8×1015/m2, the polycrystalline cubic boron nitride comprises a plurality of crystal grains, and the plurality of crystal grains have a median diameter d50 of an equivalent circle diameter of less than 100 nm.

Abstract: A cubic boron nitride sintered material includes 40% by volume or more and 96% by volume or less of cubic boron nitride grains and 4% by volume or more and 60% by volume or less of a binder phase, and the cubic boron nitride grains have a dislocation density of less than 1×105/m2.

Abstract: A polycrystalline cubic boron nitride comprising 96% by volume or more of cubic boron nitride, wherein the cubic boron nitride has a dislocation density of 8×1015/m2 or less, the polycrystalline cubic boron nitride comprises a plurality of crystal grains, and the plurality of crystal grains have a median diameter d50 of an equivalent circle diameter of less than 100 nm.