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 Al.sub.xCr.sub.(1-x)N, the layer B being composed of Al.sub.yTi.sub.(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.

Described are diffusion barriers that are effective to inhibit the flow and release of impurities present in a solid material, from a surface of the solid material, as well articles having a diffusion barrier on a surface thereof, methods of preparing articles that include a diffusion barrier on a surface, equipment that includes an article having a diffusion barrio on a surface, and methods of using the articles and equipment; the diffusion barrier include at least two different barrier materials.

In the surface-coated cutting tool, a Ti compound layer containing at least nitrogen and carbon is formed on a surface of cutting tool substrate, a nitrogen concentration in the Ti compound layer, in a case of being measured in a direction perpendicular to the surface of the cutting tool substrate in a vicinity of a cutting edge, gradually increases as a distance from cutting tool substrate increases within a range of 0.20 μm from the surface of the cutting tool substrate toward the Ti compound layer, an average concentration gradient of the nitrogen concentration is 20 at %/μm or more and 300 at %/μm or less, and an average nitrogen concentration in the Ti compound layer in the vicinity of the cutting edge is lower than an average nitrogen concentration in the Ti compound layer at a position of a flank face away from the cutting edge by 3 at % or more.

A chain component of a chain for transmitting a force includes a steel-based substrate and a hard material layer on an external side of the steel-based substrate. The hard material layer contains metal nitrides and the metal carbide content in the hard material layer decreases toward the external side of the hard material layer.

A chain component of a chain for power transmission coated with a layer of hard material includes a substrate based on steel and a layer of hard material on an outer surface of the substrate based on steel, with the layer of hard material containing metal nitrides and the C mass concentration in the layer of hard material decreasing in the direction toward the outer surface of the layer of hard material.

A process for producing a hard material layer on a substrate. A multilayer coating system is applied to the substrate by alternate deposition of CrTaN and AlTiN by way of physical vapor deposition (PVD). The CrTaN and/or the AlTiN are preferably deposited from a composite target.

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 Al.sub.xCr.sub.(1-x)N, the layer B being composed of Ti.sub.yAl.sub.zSi.sub.(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 0.5x0.8, y has a range of 0.5y<0.71, z has a range of 0.29z<0.5, and 1yz has a range of 0<1yz0.1.

An ion source enhanced AlCrSiN coating for a cutting tool is provided. The ion source enhanced AlCrSiN coaling has gradient Si content and grain size, including sequentially an AlCrSiN working layer, an interlayer and an AlCrN bottom layer in order from a surface of the coating to a substrate, wherein from the AlCrN bottom layer to the AlCrSiN working layer, Si content in the interlayer is gradually increased, and the interlayer has a texture that changes from coarse columnar crystals to fine nanocrystals and amorphous body. A texture of the coating, in which the grain size is gradually decreased, sequentially includes coarse columnar crystals, fine columnar crystals and fine equiaxed crystals. A method for preparing the ion source enhanced AlCrSiN coating with the gradient Si content and grain size is provided as well as a cutting tool having the coating deposited thereon.

Artificial lift pump components such as couplings are disclosed, all having a body formed from a selected material, the body having an inner diameter and an outer diameter, a first surface treatment introducing carbon, nitrogen, boron into the material to form a first and hard layer, and a second layer defined as an deposited coating to the first layer that is also made of a carbon, nitrogen, or boron and is further characterized as being ceramic like (hard) and having a low-friction.

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.