Abstract: A metal member for magnetic storage medium includes an aluminum alloy substrate, and a nonmagnetic layer formed on at least one surface of the aluminum alloy substrate, and the nonmagnetic layer comprises a Ni—Cu—P based alloy containing 5 mass % to 50 mass % Cu and 100 ppm to 1000 ppm Pb.

Abstract: A method of preparing a hard disc comprising steps of:immersing an aluminum or aluminum alloy substrate in a zincate solution containing a zinc compound, an alkali hydroxide, and at least one amine to thereby form a zincate film on the surface of the substrate,immersing the zincate film-formed substrate in an electroless nickel plating solution comprising a water-soluble nickel salt, a complexing agent, and a hypophosphite to thereby form a nickel--phosphorus alloy layer on the surface of the zincate film-coated substrate, and forming a magnetic layer on the nickel--phosphorus alloy layer.

Abstract: An amine, such as a triethanol amine or ethylenediamine is added to an alkaline electroless gold plating solution comprising a gold salt and a boron-based reducing agent to deposit a gold film having good appearance and high throwing power on a workpiece at a high deposition rate.