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: A cutting tool comprising a base material and a coating, wherein the coating includes a first layer having a multilayer structure in which a first unit layer and a second unit layer are alternately stacked; a thickness of the first unit layer is 2 to 50 nm; a thickness of the second unit layer is 2 to 50 nm; a thickness of the first layer is 1.0 ?m or more and 20 ?m or less, the first unit layer is composed of TiaAlbBcN, and the second unit layer is composed of TidAleBfN, wherein 0.49?a?0.70, 0.19?b?0.40, 0.10?c?0.20, a+b+c=1.00, 0.39?d?0.60, 0.29?e?0.50, 0.10<f?0.20, d+e+f=1.00, 0.05?a-d?0.20, and 0.05?e-b?0.20 are satisfied, and a percentage of the number of atoms of titanium to the total number of atoms of titanium, aluminum and boron is 45% or more in the first layer.

Abstract: A turning tool includes: a holder portion; and a cutting edge portion fixed to the holder portion, wherein the cutting edge portion is composed of a synthetic single-crystal diamond, and the cutting edge portion has a nose curvature having a curvature radius of more than or equal to 0.1 mm and less than or equal to 1.2 mm, and the nose curvature satisfies at least one of a condition that a direction of a line of intersection between the rake face and a bisecting cross section of a vertex angle of the nose curvature is within ±10° relative to a <110> direction of the synthetic single-crystal diamond, and a condition that the direction of the line of intersection between the rake face and the bisecting cross section of the vertex angle of the nose curvature is within ±10° relative to a <100> direction of the synthetic single-crystal diamond.

Abstract: A sintered material includes diamond grains and a binder. A boron concentration in the diamond grains is more than or equal to 0.001 mass % and less than or equal to 0.9 mass %. A boron concentration in the binder is more than or equal to 0.5 mass % and less than or equal to 40 mass %.

Abstract: A composite sintered material includes: a plurality of diamond grains having an average grain size of less than or equal to 10 ?m; a plurality of cubic boron nitride grains having an average grain size of less than or equal to 2 ?m; and a plurality of aluminum oxide grains having an average grain size of less than or equal to 0.5 ?m; and a remainder of a binder phase, wherein at least parts of adjacent diamond grains are bound to one another, the binder phase includes cobalt, in the composite sintered material, a content of the diamond grains is from 30 to 92 volume %, a content of the cubic boron nitride grains is from 3 to 40 volume %, a content of the aluminum oxide grains is from 2 to 15 volume %, and a content of the cobalt is from 3 to 30 volume %.

Abstract: A cutting tool including a rake face, a flank face, and a cutting edge portion, comprising a substrate and an AlTiN layer, the AlTiN layer including cubic AlxTi1-xN crystal grains, Al having an atomic ratio x of 0.7 or more and 0.95 or less, the AlTiN layer including a central portion, the central portion at the rake face being occupied in area by (200) oriented crystal grains at a ratio of 80% or more, the central portion at the flank face being occupied in area by (200) oriented crystal grains at a ratio of 80% or more, the central portion at the cutting edge portion being occupied in area by (200) oriented crystal grains at a ratio of 80% or more.

Abstract: A first main trajectory represents a trajectory of a first main cutting edge obtained by revolving and projecting the first main cutting edge onto a plane including a central axis. A second main trajectory represents a trajectory of the second main cutting edge obtained by revolving and projecting the second main cutting edge onto the plane. The first main trajectory intersects the second main trajectory. A tangent to the first main trajectory at an intersection between the first main trajectory and the second main trajectory is inclined to be closer to the central axis in a direction from the first surface toward the second surface. A tangent to the second main trajectory at the intersection is inclined to be closer to the central axis in a direction from the second surface toward the first surface.

Abstract: A single-crystal diamond having a first facet plane is prepared. The single-crystal diamond is fixed to the support based on the first facet plane. An X-ray image of the single-crystal diamond is captured, the X-ray image being an X-ray image in which a crystal orientation of the single-crystal diamond is associated with an X-ray emission direction by associating the support to which the single-crystal diamond is fixed with the X-ray emission direction. A position of an inclusion of the single-crystal diamond in the single-crystal diamond is specified based on the X-ray image. It is determined whether or not a shape of the diamond tool intermediate is extractable from the single-crystal diamond with the inclusion being not included in an inclusion-excluded region. The shape of the diamond tool intermediate is extracted from the single-crystal diamond with the inclusion being not included in the inclusion-excluded region.

Abstract: A surface-coated cutting tool includes a base material and a coating film formed on a surface of the base material. The coating film includes a first alternating layer and a second alternating layer formed on the first alternating layer. The first alternating layer includes first and second layers. The second alternating layer includes third and fourth layers. One or a plurality of the first layers and one or a plurality of the second layers are layered alternately, and one or a plurality of the third layers and one or a plurality of the fourth layers are layered alternately.

Abstract: A cutting tool includes a rake face, a flank face, and a cutting edge ridge line connecting the rake face and the flank face. A portion of the rake face and a portion of the flank face adjacent to the cutting edge ridge line are made of a diamond sintered body including diamond grains. A dislocation density in the portion of the flank face is 8×1015/m2 or less. The diamond grains have an average grain size of 0.1 ?m to 50 ?m. A content ratio of the diamond grains in the diamond sintered body is 80% by volume to 99% by volume.