A device comprising: a substrate; a first coating deposited on the substrate; an intermediate coating deposited on the first coating, wherein the first coating is interposed between the substrate and the intermediate coating; and a second coating deposited on the intermediate coating, wherein the intermediate coating is interposed between the first coating and the second coating, and the second coating is outermost and black. The substrate, the first coating, the intermediate coating and the second coating define at least one of a jewelry item and a component of a jewelry item.

A method for surface treatment of a metal material in a powder state is provided, the method including obtaining a powder formed from a plurality of particles of the metal material to be treated; and subjecting the powder to an ion implantation process by directing a beam of singly-charged or multi-charged ions towards an outer surface of the particles, the beam being produced by a source of singly-charged or multi-charged ions, whereby the particles have an overall spherical shape with a radius (R). There is also provided a material in a powder state formed from a plurality of particles having a ceramic outer layer and a metal core, the particles having an overall spherical shape.

The present invention discloses a magnesium alloy surface coating method and a corrosion-resistant magnesium alloy prepared thereby. The method includes the following steps: conducting pretreatment on a magnesium alloy substrate; depositing a metal film by sputtering on the surface of the pre-treated magnesium alloy substrate; and depositing a Si.sub.3N.sub.4 film by sputtering on the surface of the magnesium alloy substrate on which the metal film is deposited. The metal is any one of Nb, Cr, and Ta. The method in the present invention can provide effective protection for a magnesium alloy, thereby improving the corrosion resistance of the magnesium alloy.

A coated substrate, includes a coating that includes, starting from the substrate in this order: a) a layer of diamond-like carbon (DLC), b) a metallic, single-ply or multi-ply layer, and c) an oxygen barrier layer, wherein the metallic, single-ply or multi-ply layer contains b1) tin or tin and at least one alloying element for tin, which are present unalloyed and/or alloyed, or b2) magnesium and at least one alloying element for magnesium, which are present unalloyed and/or alloyed. The coated substrate protects the DLC layer, as a result of which said layer can be tempered. The coating has good mechanical stability and good aging stability before heat treatment.

An engineered substrate includes a support structure comprising a polycrystalline ceramic core, an adhesion layer coupled to the polycrystalline ceramic core, and a barrier layer coupled to the adhesion layer. The engineered substrate also includes an bonding layer coupled to the support structure, a substantially single crystal layer coupled to the bonding layer, and an epitaxial gallium nitride layer coupled to the substantially single crystal layer.

A polycrystalline-diamond cutting element for a drill bit of a downhole tool. The cutting element includes a substrate and a diamond table bonded to the substrate. The diamond table includes a diamond filler with at least one leached polycrystalline diamond segment packed therein along at least one working surface thereof. The cutting element may be formed by positioning the diamond table on the substrate and bonding the diamond table onto the substrate such that the polycrystalline diamond segment is positioned along at least one working surface of the diamond table. A spark plasma sintering or double press operation may be used to bond the diamond table onto the substrate.

A thixomolding material includes: a metal body that contains Mg as a main component; and a coating portion that is adhered to a surface of the metal body via a binder and contains SiC particles containing SiC as a main component. A mass fraction of the SiC particles in a total mass of the metal body and the SiC particles is 2.0 mass % or more and 40.0 mass % or less. The binder may contain waxes. A content of the binder may be 0.001 mass % or more and 0.200 mass % or less.

This copper/ceramic bonded body includes: a copper member made of copper or a copper alloy; and a ceramic member made of silicon nitride, wherein the copper member and the ceramic member are bonded to each other, a MgN compound phase extending from a ceramic member side to a copper member side is present at a bonded interface between the copper member and the ceramic member, and at least a part of the MgN compound phase enters into the copper member.

An external part of a timepiece has a substrate that includes a base layer and a surface layer, the surface layer including Ti or stainless steel; and a coating disposed on the substrate. The coating includes an outermost layer formed primarily of TiC defining an external surface, and an interior layer formed primarily of TiC positioned between the substrate and the outermost layer. An elastic modulus of the interior layer is greater than the elasticmodulus of the outermost layer.

A polycrystalline-diamond cutting element for a drill bit of a downhole tool. The cutting element includes a substrate and a diamond table bonded to the substrate. The diamond table includes a diamond filler with at least one leached polycrystalline diamond segment packed therein along at least one working surface thereof. The cutting element may be formed by positioning the diamond table on the substrate and bonding the diamond table onto the substrate such that the polycrystalline diamond segment is positioned along at least one working surface of the diamond table. A spark plasma sintering or double press operation may be used to bond the diamond table onto the substrate.