To provide a surface-coated cutting tool exhibiting excellent wear resistance in a high-speed cutting process and having prolonged service life. The surface-coated cutting tool includes a tool substrate containing WC crystal grains and insulating grains, and a coating layer composed of a multiple nitride of Ti, Al, and V and disposed on the surface of the tool substrate. The multiple nitride is represented by a compositional formula: Ti.sub.aAl.sub.bV.sub.cN satisfying the following relations:

0.25≤a≤0.35,

0.64≤b≤0.74,

0<c≤0.06, and

a+b+c=1

(wherein each of a, b, and c represents an atomic proportion). The coating layer is characterized by exhibiting a peak attributed to a hexagonal crystal phase and a peak attributed to a cubic crystal phase as observed through X-ray diffractometry.

Adhesive compositions and methods for bonding materials with different thermal expansion coefficients is provided. The adhesive is formulated using a flux material, a low flux material, and a filler material, where the filler material comprises particulate from at least one of the two components being bonded together. A thickening agent can also be used as part of the adhesive composition to aid in applying the adhesive and establishing a desired bond thickness. The method of forming a high strength bond using the disclosed adhesive does not require the use of intermediary layer or the use of high cure temperatures that could damage one or both of the components being bonded together.

A cubic boron nitride sintered material comprises 30% by volume or more and 80% by volume or less of cubic boron nitride grains and 20% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grains having a dislocation density of 3×10.sup.17/m.sup.2 or more and 1×10.sup.20/m.sup.2 or less.

The present invention relates to a method for producing a metal-ceramic substrate (1) comprising: —providing a ceramic element (30) and at least one metal layer (10), wherein the ceramic element (30) and the at least one metal layer (10) extend along a main extension plane (HSE), —joining the ceramic element (30) to the at least one metal layer (10) to form a metal-ceramic substrate (1), in particular by means of a direct metal joining method, a hot isostatic pressing method and/or a soldering method, and —machining the at least one metal layer (10) by means of a machine tool (40) and/or laser light in order to define a geometry, at least in some portions, of a side face (15) of the at least one metal layer (10) not running parallel to the main extension plane (HSE).

A polycrystalline diamond compact including a cemented carbide substrate and a polycrystalline diamond layer bonded to the cemented carbide substrate. The polycrystalline diamond layer is nonplanar and includes a central part and a peripheral part surrounding the central part. The central part includes a protruding surface relative to the peripheral part. The protruding surface is spherical or planar. The peripheral part includes a plurality of radially-disposed ridges.

A cBN sintered compact has cubic boron nitride particles and a ceramic binder phase, and in the sintered compact, WSi.sub.2 having an average particle diameter of 10 nm to 200 nm is dispersed such that a content thereof is 1 vol % to 20 vol %. A cutting tool has the cBN sintered compact as a tool body.

An electrically conductive ceramic composite conductor configured for downhole operations includes a first portion formed from an electrically non-conductive ceramic material having a first coefficient of thermal expansion (CTE). The first portion includes an outer surface. A second portion is disposed radially inwardly of the outer surface. The second portion is formed from an electrically conductive ceramic material having a second CTE that is substantially similar to the first CTE.

A ceramic structure includes a base body, and a thermoelectric device having a part in directly contact with the base body. The base body is a ceramic consisting of aluminum oxide. The thermoelectric device comprises a conductor part that is a sintered body having an alloy of tungsten and rhenium, as a main component, and including nickel oxide, aluminum oxide and silicon dioxide.

Adhesive compositions and methods for bonding materials with different thermal expansion coefficients is provided. The adhesive is formulated using a flux material, a low flux material, and a filler material, where the filler material comprises particulate from at least one of the two components being bonded together. A thickening agent can also be used as part of the adhesive composition to aid in applying the adhesive and establishing a desired bond thickness. The method of forming a high strength bond using the disclosed adhesive does not require the use of intermediary layer or the use of high cure temperatures that could damage one or both of the components being bonded together.

A cubic boron nitride sintered material comprises 30% by volume or more and 80% by volume or less of cubic boron nitride grains and 20% by volume or more and 70% by volume or less of a binder phase, the cubic boron nitride grains having a dislocation density of 3×10.sup.17/m.sup.2 or more and 1×10.sup.20/m.sup.2 or less.