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.

The present disclosure relates to a method of treating a cutting tool of a cemented carbide or cermet substrate, wherein the cutting tool is subjected to shot peening at a temperature of or above 100° C. The cutting tool typically has a rake face, a flank face and a cutting edge extending therebetween. The shot peening is performed at least on the rake face of the cutting tool. The present disclosure also relates to a cutting tool treated with the method.

A cutting tool, comprising a substrate having a cutting surface and a coating adhered to the cutting surface in a solid state, wherein the coating includes a soft metal and is capable of melting and functioning as an in-situ liquid lubricant when the cutting tool is applied in a machining operation. Also, a method of applying a coating to a cutting tool, comprising receiving a premachining workpiece, the premachining workpiece formed of a coating material including a soft metal; and machining the premachining workpiece with the cutting tool such that a layer of the coating material adheres to a cutting surface of the cutting tool in a solid state.

A hard coating film of a coated cutting tool contains Al within a range of 70 at % to 80 at % and Ti within a range of 20 at % to 30 at % with respect to a total amount of metallic (including metalloid) elements, and contains Ar of 0.50 at % or less with respect to a total amount of the metallic elements (including metalloid) and nonmetallic elements. The film has a diffraction peak due to each of a TiN (111) plane, a TiN (200) plane, and a TiN (220) plane of an fcc structure and an AlN (100) plane and an AlN (002) plane of a hcp structure, in which the diffraction peak of the TiN (200) plane indicates a maximum intensity and an intensity of the diffraction peak due to the TiN (111) plane is next thereafter. The average crystal grain size is within a range of 5 nm to 50 nm.

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.

A coated cutting tool includes a body and a hard and wear resistant coating on the body. The coating has at least one NbN layer with a thickness between 0.2 m and 15 m, wherein the NbN layer includes a phase mixture of a cubic phase, c-NbN, and a hexagonal phase, h-NbN.

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.

A coated cutting tool comprising a substrate and a coating layer formed on a surface of the substrate, wherein: the coating layer comprises at least one -type aluminum oxide layer; and, in the -type aluminum oxide layer, a texture coefficient TC (0,0,12) of a (0,0,12) plane is from 4.0 or more to 8.4 or less, and a texture coefficient TC (1,2,11) of a (1,2,11) plane is from 0.5 or more to 3.0 or less.

Provided is a surface-coated cutting tool including a base material and a coating including a super-multilayer-structure layer where A layers and B layers different from the A layers in composition are alternately laminated. The super-multilayer-structure layer includes an X area and a Y area those are alternately repeated. In the X area, A layers having a thickness A.sub.X and B layers having a thickness B.sub.X are alternately laminated. In the Y area, A layers having a thickness A.sub.Y and B layers having a thickness B.sub.Y are alternately laminated. The thickness A.sub.X is larger than the thickness A.sub.Y, and the thickness B.sub.X is smaller than the thickness B.sub.Y. Each of the A layers and the B layers comprising one or more elements selected from a group consisting of Ti, Al, Cr, Si, Ta, Nb, and W, and one or more elements selected from a group consisting of C and N.

A small-diameter drill in which is a double margin having a diameter of 2 mm or less and a ratio of a margin length to a diameter of 3 or more, in which the margin length L in an axial direction from an outer peripheral end of a cutting edge to the rear ends of first and second margin parts and a ratio L/D to a diameter D are 3 or more, in which at least a surface of a chip discharge groove is provided with a hard coating made of nitride, in which a surface of the hard coating in the chip discharge groove has skewness (Ssk) defined in ISO25178 of less than 0, and in which the number of droplets having an equivalent circle diameter of 1.0 m or more is 5 or less per 100 m.sup.2 in cross-section observation of the hard coating.