Abstract: A rotary cutting tool includes a base material, a first diamond layer, and a second diamond layer. The base material includes a head portion, a body portion, and a shoulder portion defining a boundary portion between the head portion and the body portion. The first diamond layer covers the body portion and the shoulder portion and exposes the head portion. The second diamond layer covers the head portion, is provided on the first diamond layer in the shoulder portion, and does not cover the body portion.

Abstract: A cutting tool comprises a substrate and a coating that coats the substrate, the coating including an ?-alumina layer, the ?-alumina layer including crystal grains of ?-alumina, the ?-alumina layer including a lower portion and an upper portion, the upper portion being occupied in area at a ratio of 50% or more by crystal grains of ?-alumina having (006) plane with a normal thereto having a direction within ±15° with respect to a direction of a normal to the second interface, the lower portion being occupied in area at a ratio of 5% or more and less than 50% by crystal grains of ?-alumina having (012) plane, (104) plane, (110) plane, (113) plane, (116) plane, (300) plane, (214) plane and (006) plane each with a normal thereto having a direction within ±15° with respect to the direction of the normal to the second interface.

Abstract: Provided is a cubic boron nitride sintered body including more than or equal to 85 volume percent and less than 100 volume percent of cubic boron nitride particles, and a remainder of a binder, wherein the binder contains WC, Co, and an Al compound, the binder contains W2Co21B6, and, when IA represents an X-ray diffraction intensity of a (111) plane of the cubic boron nitride particles, IB represents an X-ray diffraction intensity of a (100) plane of the WC, and IC represents an X-ray diffraction intensity of a (420) plane of the W2Co21B6, a ratio IC/IA of the IC to the IA is more than 0 and less than 0.10, and a ratio IC/IB of the IC to the IB is more than 0 and less than 0.40.

Abstract: A manufacturing method, a manufacturing apparatus, a computer readable recording medium, and a program for manufacturing a machine component having a rotation symmetry plane are provided.

Abstract: A cutting insert has a top surface, a seating surface, and an outer peripheral surface. The cutting edge includes a corner cutting edge portion, a first cutting edge portion, and a second cutting edge portion. The top surface includes a first rake face, a second rake face, a third rake face, a front side surface, an upper surface, a first side surface, and a second side surface. A ridgeline between the first side surface and the second side surface is continuous to the upper surface. When seen in a direction perpendicular to the seating surface, a width of a boundary between the front side surface and the third rake face is larger than a width of a boundary between the front side surface and the upper surface.

Abstract: A cutting tool incudes 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 TiyAlzSi(1-y-z)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, y has a range of 0.5?y<0.71, z has a range of 0.29?z<0.5, and 1?y?z has a range of 0<1?y?z?0.1.

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 cutting insert includes a cylindrical body portion, a cutting portion, a first fitting portion, a second fitting portion, and a third fitting portion. The cutting portion includes a rake face and a flank face. A ridgeline between the rake face and the flank face constitutes a cutting edge. When viewed in the axial direction, the cutting portion is provided opposite to the third fitting portion relative to the insertion hole. When viewed in the axial direction, a straight line extending through an outer circumferential end of the cutting edge and a center of the insertion hole overlaps with the third fitting portion and is located between the first fitting portion and the second fitting portion. A third central angle is smaller than a first central angle and is smaller than a second central angle.

Abstract: A surface-coated cutting tool includes a base material and a coating. A hard layer in the coating includes a plurality of crystal grains having a sodium chloride-type crystal structure. The crystal grain has a layered structure in which a first layer composed of nitride or carbonitride of AlxTi1-x and a second layer composed of nitride or carbonitride of AlyTi1-y are alternately stacked. The total thickness of the first layer and the second layer adjacent to each other is 3 nm or more and 40 nm or less. An angle of intersection between a normal direction to (111) plane that is a crystal plane of the crystal grain and the normal direction to the surface of the base material, an area ratio of the crystal grains having the angle of intersection of 0 degree or more to less than 10 degrees is 40% or more.

Abstract: A cemented carbide comprises a first hard phase comprising tungsten carbide particles and a binder phase including Co and Cr. In any surface or any cross section of the cemented carbide, a region in which there is a distance X of 5 nm or less between surfaces respectively of tungsten carbide particles adjacent to each other, with the surfaces facing each other along a length L of 100 nm or more, is referred to as a WC/WC interface, and a ratio C(R)/C(C) has an average value of 0.17 or more, where C(R) and C(C) represent peak values of atomic percentages of Cr and Co, respectively, at a WC/WC interface having a distance X of 1 nm or more and 5 nm or less and having therein an atomic percentage of Co higher than an average value of atomic percentages of Co in the tungsten carbide particles+2 at %.

Abstract: A surface coated cutting tool comprises a base material and a coating layer that coats the base material, the coating layer including an alternate layer composed of a first unit layer and a second unit layer alternately stacked, the first unit layer being composed of a nitride containing aluminum and zirconium, in the first unit layer, when the total number of metal atoms constituting the first unit layer is represented as 1, a ratio thereto of the number of atoms of the zirconium being not less than 0.65 and not more than 0.95, the second unit layer being composed of a nitride containing titanium and aluminum, in the second unit layer, when the total number of metal atoms constituting the second unit layer is represented as 1, a ratio thereto of the number of atoms of the aluminum being larger than 0.40 and not more than 0.70.

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 (200) 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 (200) oriented AlxTi1-xN crystal grains at a ratio of 80% or more.

Abstract: An oil hole reamer includes an oil passage extending inside a tool main body along an axis of the tool main body, and an oil hole extending radially outward from the oil passage to an outer circumference of the tool main body. An oil outlet of the oil hole is formed to be open toward a position corresponding to a corner at which a tip cutting edge intersects an outer-circumference cutting edge and to cause at least part of the oil outlet to be open to the outer-circumference flank face.

Abstract: The upper surface includes a first breaker projection face extending along the first side surface, a second breaker projection face extending along the second side surface, and a rake face located between the first breaker projection face and the second breaker projection face in top view. In a direction from the rear surface to the front surface, a first front end of the first breaker projection face is located ahead of a second front end of the second breaker projection face. A cutting edge has a first cutting edge portion and a second cutting edge portion. In a direction perpendicular to the reference surface, the second breaker projection face is lower than the first breaker projection face, and a boundary between the first cutting edge portion and the second cutting edge portion is lower than the second breaker projection face.

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: Provided is a cutting tool including a base material including a flank face and a coating layer that coats the flank face, the coating layer including a matrix region and metal particulates, the matrix region being made of a compound represented by (AlxTiyX1-x-y)CvOwN1-v-w, where X representing at least one element selected from the group consisting of chromium, silicon, niobium, tantalum, tungsten, and boron, the metal particulates containing aluminum or titanium as a constituent element, the metal particulates having particle diameters of more than or equal to 20 nm and less than or equal to 200 nm, a number of the metal particulates being more than or equal to 12 and less than or equal to 36 in a field of view of 3 ?m×4 ?m in a cross section parallel to a direction of a normal to an interface of the coating layer.

Abstract: Provided is a cutting tool including a base material including a rake face and a coating layer that coats the rake face, the coating layer including a matrix region and metal particulates, the matrix region being made of a compound represented by (AlxTiyX1?x?y)CvOwN1?v?w, where X representing at least one element selected from the group consisting of chromium, silicon, niobium, tantalum, tungsten, and boron, the metal particulates containing aluminum or titanium as a constituent element, the metal particulates having particle diameters of more than or equal to 20 nm and less than or equal to 200 nm, a number of the metal particulates being more than or equal to 12 and less than or equal to 36 in a field of view of 3 ?m×4?m in a cross section parallel to a direction of a normal to an interface of the coating layer.

Abstract: A method for manufacturing a machine component includes determining a track of a cutting edge and feeding the cutting edge along the track. The determining a track includes calculating a coordinate (X(t), Y(t), Z(t)) of a first end portion of the cutting edge in accordance with X(t)=(Rsh(t)cos ?(t)?Xchip(t)), Y(t)=(Rsh(t)sin ?(t)?Ychip(t)), and Z(t)=(Zsh(t)?Zchip(t)), where a variable t assumes (N+1) values not smaller than 0 and not greater than 1. ?(t) represents an angle formed by a straight line connecting a point of cutting projected on an XY plane and an origin of the XY plane to each other with respect to an X axis, and ?(t) satisfies a condition tan ? ? ? ? ( t ) = tan ? ? ? · tan ? ? ? s - tan ? ? ? · tan 2 ? ? + tan 2 ? ? - tan 2 ? ? s tan ? ? ? · tan ? ? ? s + tan ? ? ? · tan 2 ? ? + tan 2 ? ? - tan 2 ? ? s .