Abstract:A process to produce amorphous Ni P alloy coatings from nickel sulfate and hypophosphite bath by electrodeposition was investigated. The influence of the concentration of phosphorous and pH in the bath, the plating temperature and the organic additives ware determined. The X ray energy dispersive spectroscopy (EDAX) was used to evaluate the composition of the alloy coatings. The alloy coatings containing over 10%～12% P(mole percent) were distinguished to be amorphous by X ray diffraction, they were found to have better corrosion resistance than the conventional Ni Cr stainless steel in 5% HCl, H₂SO₄, NaCl and NaOH solutions. The effective mechanism of organic surfactants was studied by voltammetry on a copper rotating disk electrode.

Key words: electrodeposition amorphous alloy coating nickel phosphorus