A coated cutting tool having a substrate and a coating is provided. The coating includes an inner α-Al.sub.2O.sub.3-multilayer and an outer α-Al.sub.2O.sub.3-single-layer. The thickness of the inner α-Al.sub.2O.sub.3-multilayer is less than or equal to 35% of the sum of the thickness of the inner α-Al.sub.2O.sub.3-multilayer and the thickness of the outer α-Al.sub.2O.sub.3-single-layer. The sum of the thickness of the inner α-Al.sub.2O.sub.3-multilayer and the outer α-Al.sub.2O.sub.3-single-layer is 2-15 μm. The inner α-Al.sub.2O.sub.3-multilayer consists of alternating sublayers of α-Al.sub.2O.sub.3 and sublayers of TiCO, TiCNO, AlTiCO or AlTiCNO. The inner α-Al.sub.2O.sub.3-multilayer can include at least 5 sublayers of α-Al.sub.2O.sub.3.

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.

A coated cutting tool comprises a substrate and a coating layer formed on a surface of the substrate, and has a rake face and a flank. The coating layer comprises an alternating laminate structure in which first compound layers containing AlN and second compound layers containing a compound are laminated in an alternating manner, the compound having a composition represented by formula (1) below:
(Ti.sub.1-xAl.sub.x)N  (1)
(wherein x satisfies 0.40≤x≤0.70). An average thickness T.sub.1 per first compound layer is 5 nm or more to 160 nm or less, and an average thickness T.sub.2 per second compound layer is 8 nm or more to 200 nm or less. A ratio of T.sub.1 to T.sub.2 is 0.10 or more to 0.80 or less. An average thickness T.sub.3 of the alternating laminate structure is 2.5 μm or more to 7.0 μm or less. A ratio (H/E) of hardness H to elastic modulus E is 0.065 or more to 0.085 or less at the rake face or the flank.

A coated tool includes a base and a coating film on the base. The coating film includes an Al.sub.2O.sub.3 layer, and a surface layer on the Al.sub.2O.sub.3 layer. The surface layer has a first erosion rate of 0.1 μm/min or less. The first erosion rate is obtained from measurement by causing a liquid A, in which 3 mass % of amorphous Al.sub.2O.sub.3 particles having a mean particle diameter of 1.1-1.3 μm is dispersed in purified water, to collide with the surface layer. The surface layer has a second erosion rate of 2.0 μm/min or more. The second erosion rate is obtained from measurement by causing a liquid B, in which 3 mass % of spherical Al.sub.2O.sub.3 particles having a mean particle diameter of 2.8-3.2 μm is dispersed in purified water, to collide with the surface layer.

A coated substrate has a substrate and a coating system having one or more ceramic layers. At least a first layer of one of the one or more ceramic layers is a columnar layer having as-deposited columns and intercolumn gaps. The intercolumn gaps have a mean width at least one of: at least 4.0 micrometers; and at least 1.5% of a thickness of said first layer.

A coated tool according to the present disclosure comprises a base body and a coating film. The base body contains a plurality of boron nitride particles. The coating film is located on the base body. In addition, in a case where a hardness is measured by pressing an indenter from a surface of the coating film to a depth of 20% of the coating film while changing an indentation load of the indenter, a maximum hardness difference, which is a difference between a maximum hardness and a minimum hardness of the hardness, is 4 GPa or more.

A sliding element for an internal combustion engine may include a base material having an annular external surface. The external surface may include a bonding layer, a first layer of coating, and a second layer of coating sequentially disposed thereon. The first layer of coating and the second layer of coating may include hard amorphous carbon (DLC) of a combined matrix having a plurality of sp3/sp2 bonds. The first layer of coating may include 45% sp3 bonds or less and may have a thickness of at least 10 micrometers. The second layer of coating may include at least 55% sp3 bonds and may have a thickness of at least 3 micrometers.

The present invention relates to coatings comprising or consisting of one or more ternary TM-diboride coating films. The ternary TM-diboride coating films showing exceptionally high phase stability and mechanical properties, even at high temperatures or even after exposition to high temperatures.

A coated cutting tool which has, on a surface of a substrate, a layer A of a face-centered cubic lattice structure which is a nitride or carbonitride containing 50 atom % or more of Al, 20 atom % or more of Cr, 85 atom % or more of Al and Cr, and 4 atom % or more and 15 atom % or less of Si, and a layer B provided on the layer A. The layer B is a nitride or carbon nitride which contains 70 atom % or more and 90 atom % or less of Ti, 5 atom % or more and 20 atom % or less of Si, and 1 atom % or more and 10 atom % or less of Nb or Cr in terms of a total amount of metal (including metalloid) elements, and has the face-centered cubic lattice structure.

Provided is a cutting tool including a base material and a coating layer provided on the base material, the coating layer including a titanium carbonitride layer provided on the base material, an intermediate layer provided on the titanium carbonitride layer in contact therewith, and an alumina layer provided on the intermediate layer in contact therewith, the intermediate layer being composed of a compound made of titanium, carbon, oxygen, and nitrogen, the intermediate layer having a thickness of more than 1 μm, when P.sub.C1 atomic % represents an atomic ratio of the carbon in an interface between the intermediate layer and the alumina layer, and P.sub.C2 atomic % represents an atomic ratio of the carbon at a point A away from the interface by 1 μm on a side of the intermediate layer, a ratio P.sub.C1/P.sub.C2 of the P.sub.C1 to the P.sub.C2 being more than or equal to 1.03.