Provided is a surface-coated cutting tool including: a cutting tool body and a hard coating layer on a surface of the cutting tool body, wherein the hard coating layer includes a complex nitride layer of Al, Cr, Si, and Cu, the complex nitride layer of Al, Cr, Si, and Cu includes a main phase, and CrSi-rich particles and Al-rich particles that are dispersed in the main phase, the main phase satisfies 0.150.40, 0.050.20, 0.0050.05, and 0.45x0.60, the CrSi-rich particles satisfy 0.200.55, 0.200.55, 00.10, and 0.02x0.35, the Al-rich particles satisfy 0.100.25, 0.050.25, 00.10, and 0.02x0.35 in a composition formula: (Al.sub.1---Cr.sub.Si.sub.Cu.sub.).sub.1-xN.sub.x), and an occupancy area ratio of the CrSi-rich particles having a major axis of 100 nm or more is 0.20 to 2.0 area %; and an occupancy area ratio of the Al-rich particles having a major axis of 100 nm or more is 0.50 to 3.0 area %.

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.

A sintered material includes cubic boron nitride grains and a binder, a grain size D50 of the cubic boron nitride grains when a cumulative value of the cubic boron nitride grains is 50% in an area-based grain size distribution being more than 0.5 m and less than or equal to 5 m, more than or equal to 70 volume % and less than or equal to 98 volume % of the cubic boron nitride grains being included in the sintered material, the binder being composed of A.sub.1-xCr.sub.xN, where 0x1, and a remainder, the remainder being composed of at least one of a first element and a compound including the first element and a second element, the first element being one or more elements selected from a group consisting of W, Co, Ni, Mo, Al, and Cr, the second element being one or more elements selected from a group consisting of nitrogen, carbon, oxygen, and boron.

Provided is a method for producing a polycrystalline diamond body, the method including a first step of heat-treating a powder of high-pressure-phase carbon at higher than or equal to 1300 C. to obtain a heat-treated carbon powder, and a second step of sintering the heat-treated carbon powder under conditions of greater than or equal to 12 GPa and less than or equal to 25 GPa and higher than or equal to 1200 C. and lower than or equal to 2300 C. to obtain a polycrystalline diamond body.

A cutting tip, a cutting tool and a gear edge cut-off device have greater ease-of-use than the conventional art. The cutting tip has a shaft portion supported linearly movably and forwardly biased in a linearly moving direction, an angular base portion provided at a front end of the shaft portion and having a pair of skirt faces and a ridge portion that extends obliquely with respect to the linearly moving direction, a groove depressed near the ridge portion of the skirt face, a blade edge on the cutting blade, positioned on a border line between the ridge portion and the groove, a rake face provided on the cutting blade and positioned further toward the groove side than the blade edge, and a flank face positioned further toward the ridge portion side than the blade edge and jutting out in the forward direction as it retracts from the blade edge.

A cutting tip, a cutting tool and a gear edge cut-off device have greater ease-of-use than the conventional art. The cutting tip has a shaft portion supported linearly movably and forwardly biased in a linearly moving direction, an angular base portion provided at a front end of the shaft portion and having a pair of skirt faces and a ridge portion that extends obliquely with respect to the linearly moving direction, a groove depressed near the ridge portion of the skirt face, a blade edge on the cutting blade, positioned on a border line between the ridge portion and the groove, a rake face provided on the cutting blade and positioned further toward the groove side than the blade edge, and a flank face positioned further toward the ridge portion side than the blade edge and jutting out in the forward direction as it retracts from the blade edge.

A sintered material includes a first material and a second material, the first material being partially stabilized ZrO.sub.2 having a crystal grain boundary or crystal grain in which 5 to 90 volume % of Al.sub.2O.sub.3 is dispersed with respect to a whole of the first material, the second material including at least one of SiAlON, silicon nitride and titanium nitride, the sintered material including 1 to 50 volume % of the first material.

An apparatus for smoothing an inner toothing and/or an outer toothing of a component part. At least two radially adjustable smoothing gears, which engage in the inner toothing and/or outer toothing, are rotatably arranged inside the inner toothing and/or outside of the outer toothing. During smoothing, the component part is not firmly clamped but rather only rests loosely on a support. A thrust ring is provided at least at one of the smoothing gears for limiting axial movements of the component part, which occur during smoothing.

An apparatus for smoothing an inner toothing and/or an outer toothing of a component part. At least two radially adjustable smoothing gears, which engage in the inner toothing and/or outer toothing, are rotatably arranged inside the inner toothing and/or outside of the outer toothing. During smoothing, the component part is not firmly clamped but rather only rests loosely on a support. A thrust ring is provided at least at one of the smoothing gears for limiting axial movements of the component part, which occur during smoothing.

Method for the face-side chamfering of gear teeth of a workpiece (20) in a CNC-controlled multiaxis machine including inserting a tool (100) in the multiaxis machine, wherein the tool (100) has at least one cutting tooth (111) having a first rake face and a second rake face, driving the tool (100) in a first rotational direction, executing first CNC-controlled relative movements while the tool (100) rotates in the first rotational direction to chamfer a first face-side edge (24) of a first tooth of the gear teeth using the first rake face of the tool (100), and executing second CNC-controlled relative movements while the tool (100) rotates in the first rotational direction, to chamfer a second face-side edge (25) of the first tooth or another tooth of the gear teeth using the second rake face of the tool (100), and apparatus therefor.