Abstract: A cutting tool according to an aspect of the present disclosure includes a cutting edge portion which contains at least one of cubic boron nitride and polycrystalline diamond. The cutting edge portion includes a rake face, a flank face, and a cutting edge. The flank face is contiguous to the rake face. The cutting edge is provided as a ridge line between the rake face and the flank face. The radius of curvature of the cutting edge is 2 ?m or more and 8 ?m or less.

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: The polycrystalline cubic boron nitride contains a cubic boron nitride at a content greater than or equal to 98.5% by volume, and has an area rate S1 of crystal grains, the crystal grains having an equivalent circle diameter greater than or equal to 1 ?m, less than or equal to 20 area % at a cross section of the polycrystalline cubic boron nitride as observed with a scanning electron microscope at a magnification of 10,000.

Abstract: A cutting insert has a seating surface, an outer peripheral surface, a top surface, and an attachment hole. The cutting edge includes a curved cutting corner edge portion, a first cutting edge portion, and a second cutting edge portion. The top surface includes a first rake face contiguous to the first cutting edge portion, a second rake face contiguous to the second cutting edge portion, and a third rake face contiguous to the cutting corner edge portion and also contiguous to the first and second rake faces. The third rake face has a first region contiguous to the first rake face and a second region contiguous to the second rake face. The first rake face and the first region each have a rake angle which is a positive angle. The second rake face and the second region each have a rake angle which is a negative angle.

Abstract: A cutting insert includes a bottom surface, a top surface opposite to the bottom surface, and a cutting edge portion. The cutting edge portion is located on the same side as the top surface. The cutting edge portion is formed of a sintered material including cubic boron nitride particles. A volume ratio of the cubic boron nitride particles to the sintered material is more than or equal to 50 percent. The cutting edge portion includes a rake face, a flank face contiguous to the rake face, and a cutting edge located along a ridgeline between the rake face and the flank face. The rake face is inclined toward the bottom surface so that a distance from the rake face to the bottom surface decreases gradually toward the cutting edge.

Abstract: A cutting tool includes a substrate and a coating that coats a surface of the substrate, the coating including a multilayer structure layer composed of at least one layer A and at least one layer B alternately deposited from a side closer to the substrate toward a side closer to a surface, the layer A having an average composition of AlxCr(1-x)N, the layer B being composed of AlyTi(1-y)N, the layer A being composed of a domain region and a matrix region, the domain region having a composition ratio of Cr larger than that of Cr of the matrix region, wherein x has a range of 0.5?x?0.8 and y has a range of 0.5?y?0.7.

Abstract: A sintered material includes a cubic boron nitride, a zirconium-containing oxide, a zirconium-containing nitride, and an aluminum-containing oxide, wherein the zirconium-containing nitride includes both or one of ZrN and ZrON, and the aluminum-containing oxide includes a type Al2O3.

Abstract: A cutting tool includes a base material. The base material is a cemented carbide or a cermet. A surface of the base material includes a rake face, a flank face, and a cutting edge face connecting the rake face to the flank face. The base material has an oxygen concentration of less than or equal to 1 at. % at a depth position of 0.4 ?m from the cutting edge face.

Abstract: A surface-coated cutting tool includes a substrate and a coating formed on a surface of the substrate, the coating including one or two or more layers, at least one of the layers being an Al-rich layer including hard particles, the hard particle having a sodium chloride type crystal structure, and including a first unit phase in a form of a plurality of lumps and a second unit phase interposed between the lumps of the first unit phase, the first unit phase being composed of a nitride or carbonitride of AlxTi1-x, the first unit phase having an atomic ratio x of Al of 0.7 or more and 0.96 or less, the second unit phase being composed of a nitride or carbonitride of AlyTi1-y, the second unit phase having an atomic ratio y of Al exceeding 0.5 and less than 0.7.

Abstract: A cutting tool includes a substrate and a coating that covers the substrate, the coating includes an ?-Al2O3 layer, and the ?-Al2O3 layer has an orientation index TC(0 0 12) of a (0 0 12) plane not smaller than 4 and not larger than 8.5, an orientation index TC(2 0 14) of a (2 0 14) plane not smaller than 0.5 and not larger than 3, and a total of the orientation index TC(0 0 12) and the orientation index TC(2 0 14) not larger than 9.

Abstract: A surface-coated cutting tool having a rake face and a flank face includes a base material and a coating formed on the base material. The base material is a cemented carbide or a cermet. The coating includes an aluminum oxide layer containing a plurality of aluminum oxide crystal grains. The aluminum oxide layer includes: a first region made up of a region A on the rake face and a region B on the flank face; a second region on the rake face except for the region A; and a third region on the flank face except for the region B. The aluminum oxide layer satisfies a relation: b?a>0.5, where a is an average value of TC(110) in the first region in texture coefficient TC(hkl), and b is an average value of TC(110) in the second or third region in texture coefficient TC(hkl).

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 less than 0.95, the AlTiN layer including a central portion, the central portion at the rake face being occupied in area by (111) oriented AlxTi1-xN crystal grains at a ratio of 50% or more and less than 80%, the central portion at the cutting edge portion being occupied in area by (111) oriented AlxTi1-xN crystal grains at a ratio of 80% or more.

Abstract: A diamond die includes a diamond provided with a hole for drawing a wire material, the diamond being a CVD single-crystal diamond, an axis of the hole being inclined relative to a normal direction of a crystal plane of the diamond.

Abstract: A surface-coated cutting tool includes a substrate composed of cemented carbide and a coating film. The coating film includes an intermediate layer in contact with the substrate and an upper layer formed on the intermediate layer. The upper layer is made up of a single layer consisting of an upper base layer which is a layer in contact with the intermediate layer or multiple layers constituted of two or more layers. A mismatch in lattice interplanar spacing in an interface region between the substrate and the intermediate layer is not higher than 65% of a theoretical value of a mismatch in lattice interplanar spacing between the substrate and the upper base layer. A mismatch in lattice interplanar spacing in an interface region between the intermediate layer and the upper base layer is not higher than 65% of the theoretical value of the mismatch in lattice interplanar spacing between the substrate and the upper base layer.

Abstract: A surface-coated cutting tool has a rake face and a flank face, and includes a base material and a coating formed on the base material. The base material has a cutting edge face connecting the rake face to the flank face. The coating includes an aluminum oxide layer containing a plurality of aluminum oxide crystal grains. The aluminum oxide layer includes: a first region made up of a region A on the rake face and a region B on the flank face; a second region on the rake face except for the region A; and a third region on the flank face except for the region B. The aluminum oxide layer satisfies a relation: b?a>0.5, where a is an average value of TC(006) in the first region in texture coefficient TC(hkl), and b is an average value of TC(006) in the second or third region in texture coefficient TC(hkl).

Abstract: A surface-coated cutting tool includes a base material and a coating film provided on a surface of the base material, wherein the coating film includes a first alternating layer provided on the base material and a second alternating layer provided on the first alternating layer, the first alternating layer includes A and B layers, the second alternating layer includes C and D layers, each of one or plurality of the A layers is composed of a nitride or carbonitride of AlaCrbM1(1-a-b), each of one or plurality of the B layers is composed of a nitride or carbonitride of AlcTidM2(1-c-d), each of one or plurality of the C layers is composed of a nitride or carbonitride of TieSifM3(1-e-f), and each of one or plurality of the D layers is composed of a nitride or carbonitride of TigSihM4(1-g-h).

Abstract: A surface-coated cutting tool includes a base material and a coating formed on the base material. The base material is a cemented carbide or a cermet. A surface of the base material includes a rake face, a flank face, and a cutting edge face connecting the rake face to the flank face. The base material has an oxygen concentration of less than or equal to 1 at. % at a depth position of 0.4 ?m from the cutting edge face. The coating includes a hard layer. A topmost layer in the hard layer has a compressive stress of more than or equal to 1.5 GPa in absolute value.

Abstract: A surface-coated cutting tool includes a substrate and a coating that is disposed on the substrate and formed so as to cover at least a portion of a flank face, in which the coating includes an inner layer and an outer layer formed on the inner layer, the inner layer is formed of at least one layer and includes an aluminum oxide layer as a layer in contact with the outer layer, the outer layer has a multilayer structure that includes three or more layers stacked on top of one another, and each of the layers that constitute the multilayer structure contains titanium.

Abstract: A cutting insert includes a bottom surface, a top surface opposite to the bottom surface, and a cutting edge portion. The cutting edge portion is located on the same side as the top surface. The cutting edge portion is formed of a sintered material including cubic boron nitride particles. A volume ratio of the cubic boron nitride particles to the sintered material is more than or equal to 50 percent. The cutting edge portion includes a rake face, a flank face contiguous to the rake face, and a cutting edge located along a ridgeline between the rake face and the flank face. The rake face is inclined toward the bottom surface so that a distance from the rake face to the bottom surface decreases gradually toward the cutting edge.

Abstract: An end mill has a shank and a cutting edge main body portion. The cutting edge main body portion is provided on the shank and has a coolant supply path. The cutting edge main body portion includes a trailing end surface on a side of the shank, and a leading end surface opposite to the trailing end surface. The coolant supply path has a tapered portion which widens in a direction from the trailing end surface toward the leading end surface.