Abstract: A cBN sintered material comprising cBN particles and a binder phase, in which the binder phase contains AlN and AlB2, a content proportion of cBN particles is 70 to 97 vol %, cBN sintered material has a volume resistivity up to 5×10?3 ?cm, a rate of a peak intensity derived from Al with respect to a peak intensity derived from cBN particles is less than 1.0%, cBN particles include fine particles and coarse particles, coarse particles optionally include ultra-coarse particles, with respect to the entire cBN particles, a content proportion ? of fine particles is from 10 vol %, a content proportion ? of coarse particles is from 30 vol %, a content proportion ? of ultra-coarse particles is 25 vol % or less, and a total of the content proportion ? of fine particles and the content proportion ? of coarse particles is 50 to 100 vol %.

Abstract: A cubic boron nitride sintered material comprises cubic boron nitride particles and a bonding material, wherein the bonding material comprises at least one first metallic element selected from the group consisting of titanium, zirconium, vanadium, niobium, hafnium, tantalum, chromium, rhenium, molybdenum, and tungsten; cobalt; and aluminum; the cubic boron nitride sintered material has a first interface region sandwiched between an interface between the cubic boron nitride particles and the bonding material, and a first virtual line passing through a point 10 nm apart from the interface to the bonding material side; and when an element that is present at the highest concentration among the first metallic elements in the first interface region is defined as a first element, an atomic concentration of the first element in the first interface region is higher than an atomic concentration of the first element in the bonding material excluding the first interface region.

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: The cubic boron nitride sintered material is a cubic boron nitride sintered material comprising: cubic boron nitride particles in an amount of 70 vol % or more and less than 100 vol %, and a bonding material, wherein the bonding material includes an aluminum compound, and includes cobalt as a constituent element; the cubic boron nitride sintered material has a first region in which a space between adjacent cubic boron nitride particles is 0.1 nm or more and 10 nm or less; and when the first region is analyzed by using an energy dispersive X-ray analyzer equipped with a transmission electron microscope, the atom % of aluminum in the first region is 0.1 or more.

Abstract: A cutting tool according to the present disclosure has a rake face, a flank face, and a cutting edge. The cutting edge is located between the rake face and the flank face. The cutting tool includes a substrate composed of a cubic boron nitride sintered material, and an oxide layer that covers the substrate and that constitutes at least part or whole of the rake face, the flank face, and the cutting edge. The oxide layer includes at least one element selected from a group consisting of titanium, aluminum, zirconium, and cobalt. A thickness of the oxide layer is 2 ?m or less.

Abstract: A cubic boron nitride sintered material includes cubic boron nitride and a binder. The binder includes a first material and a second material. The first material is one or two or more first chemical species each including at least one first metallic element selected from the group consisting of tungsten, cobalt, and aluminum. Each of the first chemical species is a metal, an alloy, an intermetallic compound, a compound, or a solid solution. The second material is one or two or more second chemical species each including at least one second metallic element selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum, and chromium. Each of the second chemical species is a solid solution derived from at least one selected from the group consisting of nitride, carbide, and carbonitride. In each of the second chemical species, 0.1 atom % to 10 atom % of aluminum is dissolved.

Abstract: A cubic boron nitride sintered material tool contains a plurality of cBN grains. cBN grains located on a surface of the cutting edge contain a cubic boron nitride phase, and a hexagonal boron nitride phase. When a ratio I?*/I?* between an intensity of a ?* peak derived from a ? bond of hBN in the hexagonal boron nitride phase and an intensity of a ?* peak derived from a ? bond of hBN in the hexagonal boron nitride phase and a ? bond of cBN in the cubic boron nitride phase is determined by measuring an energy loss associated with excitation of K-shell electrons of boron, the ratio I?*/I?* of the cBN grain on the surface of the cutting edge is 0.1 to 2, and the ratio I?*/I?* of the cBN grain at a depth position of 5 ?m from the surface of the cutting edge is 0.001 to 0.1.

Abstract: The cubic boron nitride sintered material is a cubic boron nitride sintered material comprising: cubic boron nitride particles in an amount of 70 vol % or more and less than 100 vol %, and a bonding material, wherein the bonding material includes an aluminum compound, and includes cobalt as a constituent element; the cubic boron nitride sintered material has a first region in which a space between adjacent cubic boron nitride particles is 0.1 nm or more and 10 nm or less; and when the first region is analyzed by using an energy dispersive X-ray analyzer equipped with a transmission electron microscope, the atom % of aluminum in the first region is 0.1 or more.

Abstract: A diamond sintered material includes diamond grains, wherein a content ratio of the diamond grains is more than or equal to 80 volume % and less than or equal to 99 volume % with respect to the diamond sintered material, an average grain size of the diamond grains is more than or equal to 0.1 ?m and less than or equal to 50 ?m, and a dislocation density of the diamond grains is more than or equal to 1.2×1016 m?2 and less than or equal to 5.4×1019 m?2.

Abstract: A cutting tool includes: a base metal provided with a seat portion; a blade edge member that is a polycrystalline diamond sintered material containing polycrystalline diamond and a binder; and a brazing material that fixes the blade edge member to the seat portion of the base metal. The blade edge member has a thickness of greater than or equal to 0.3 mm. The brazing material is disposed between a blade edge bottom face of the blade edge member and the a seat bottom face of the seat portion and is in contact with the blade edge bottom face and the seat bottom face. The flank face is located outside of the base metal with respect to the lateral face of the base metal.

Abstract: A cBN sintered material comprising cBN particles and a binder phase, in which the binder phase contains AlN and AlB2, a content proportion of cBN particles is 70 to 97 vol %, cBN sintered material has a volume resistivity up to 5×10?3 ?cm, a rate of a peak intensity derived from Al with respect to a peak intensity derived from cBN particles is less than 1.0%, cBN particles include fine particles and coarse particles, coarse particles optionally include ultra-coarse particles, with respect to the entire cBN particles, a content proportion ? of fine particles is from 10 vol %, a content proportion ? of coarse particles is from 30 vol %, a content proportion ? of ultra-coarse particles is 25 vol % or less, and a total of the content proportion ? of fine particles and the content proportion ? of coarse particles is 50 to 100 vol %.

Abstract: cubic boron nitride sintered material including 90.0% by mass or more and 99.5% by mass or less of cubic boron nitride and 0.5% by mass or more and 10.0% by mass or less of silicon, wherein the cubic boron nitride sintered material has a total content of the cubic boron nitride and the silicon of 94.0% by mass or more and 100% by mass or less.

Abstract: A cutting tool comprising a substrate and a coating film disposed on the substrate, wherein the coating film comprises a first layer; the first layer has a thickness of 0.2 ?m or more and 9 ?m or less; the first layer is composed of Ti(1-x-y)AlxMyN, wherein M is at least one element such as zirconium; in the first layer, x and y change along the thickness direction of the first layer; a maximum value of x, xmax, is 0.20 or more and 0.70 or less; a minimum value of x, xmin, is 0 or more and 0.6 or less; xmax and xmin satisfy 0.01?xmax?xmin?0.7; a maximum value of y, ymax, is 0.01 or more and 0.20 or less; a minimum value of y, ymin, is 0 or more and 0.19 or less; and ymax and ymin satisfy 0.01?ymax?ymin?0.2.

Abstract: A composite sintered material includes a plurality of diamond grains, a plurality of cubic boron nitride grains, and a remainder of a binder phase, wherein the binder phase includes cobalt, a content of the cubic boron nitride grains in the composite sintered material is more than or equal to 3 volume % and less than or equal to 40 volume %, and an average length of line segments extending across continuous cubic boron nitride grains in appropriately specified straight lines extending through the composite sintered material is less than or equal to a length three times as large as an average grain size of the cubic boron nitride grains.

Abstract: A cutting tool rotates about a rotation axis, and includes a tip end portion. The tip end portion includes a partially spherical surface that is brought into contact with a workpiece. The surface is provided with a plurality of recesses disposed apart from each other. An opening edge of each of the plurality of recesses constitutes a cutting edge.

Abstract: A polycrystalline cubic boron nitride comprising 99.5% by volume or more of cubic boron nitride, wherein the polycrystalline cubic boron nitride has a heat conductivity of 300 W/mK or more, the polycrystalline cubic boron nitride has a carbon content of 100 ppm or more and 1000 ppm or less in terms of mass, 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 0.9 ?m or more and 10 ?m or less.

Abstract: A cubic boron nitride sintered material includes: more than or equal to 20 volume % and less than 80 volume % of cubic boron nitride grains; and more than 20 volume % and less than or equal to 80 volume % of a binder phase, and when a carbon content is measured from a cubic boron nitride grain into the binder phase in a direction perpendicular to an interface between the cubic boron nitride grain and the binder phase using TEM-EDX, a first region having a carbon content larger than an average value of a carbon content of the binder phase exists, the interface exists in the first region, and a length of the first region is more than or equal to 0.1 nm and less than or equal to 10 nm.

Abstract: A cutting tool includes: a main body portion composed of a cemented carbide; and a front end portion composed of a binderless cubic boron nitride polycrystal, the front end portion being joined to the main body portion. In an axial direction along a rotation axis of the main body portion, the main body portion has a first end and a second end opposite to the first end. The front end portion has a neck portion and an edge portion, the neck portion protruding from the second end along the axial direction, the edge portion being continuous to the neck portion, the edge portion being located at a location distant away from the second end relative to the neck portion in the axial direction. In the axial direction, the neck portion has a third end on the edge portion side and a fourth end opposite to the third end.