As a golden precious metal, gold has extraordinarily high chemical stability which insoluble in common acid and only soluble in aura regia, thereby, gold plating has excellent corrosion resistance, discoloration resistance, ductility, and easy to polish, then generally served as decorative plating of jewelry, watch parts, or work of art. However, gold plating is usually restricted by its high cost. In addition, gold has superior conductivity, temperature resistance, wear resistance, and easily welded, thus widely applied to precision instruments which have high demand on long-term stability of electrical parameters, include printed circuit board, integrated circuit, and electric contact. Gold plating can be classified into pure gold and karat gold according to the plating purity. There are only zinc plating and nickel plating suitable to be directly deposited on the surface of sintered Neodymium magnet, therefore, gold plated Neodymium magnet generally has a sub-layer of Ni-Cu-Ni. Besides conventional decorative purpose, jewelry, and mysterious magnetic therapy serves, gold plated Neodymium magnet is also suitable for in-body.
