The present invention relates generally to jewelry articles comprising a substrate and a metallic, external coating.

The present invention relates to a hybrid base plate and a manufacturing method therefor. Metal sheets of different materials having excellent thermal conductivity can be joined to have a thickness favorable for heat dissipation, and by arranging a metal sheet of a material with a low coefficient of thermal expansion between metal sheets with a high coefficient of thermal expansion, there is an effect of preventing warpage when manufacturing a large-area heat sink.

A bi-layer protective coating for a metal component, the bi-layer protective coating comprising a bond coating that is metallurgically fused to a substrate of the metal component, wherein the bond coating comprises one or more rare metals and a top coating that is mechanically bonded to the bond coating, wherein the top coating comprises one or more metal oxides, or one or more metal carbides.

A composite material includes: an iron-based alloy layer; an intermediate layer provided on the iron-based alloy layer; and a tungsten-containing layer provided on the intermediate layer, wherein the intermediate layer is composed of pure nickel or is an alloy that contains at least one selected from a group consisting of copper, cobalt, and iron at more than 0 mass % and less than or equal to 71 mass % in total, and that contains nickel at more than or equal to 29 mass % and less than 100 mass %.