Study of the Process for Electroless Plating of All-Bright Ni-P Alloy Coating

A lead-free process for electroless plating of all-bright nickel was established,and an all-bright Ni-P alloy coating was prepared using the established electroless plating process.At the same time,the effects of additives,inorganic slats,primary slats,plating duration,and the pH value and temperature of the plating bath on the brightness and corrosion resistance of the target Ni-P alloy coating were investigated.It was found that the electroless Ni-P alloy coating prepared using the new plating process had better brightness and corrosion resistance than the one prepared using conventional electroless nickel plating process.The introduction of the inorganic salts such as CuSO4 and TaSO4 led to an increasing in the stability of the plating bath(stability test in PdCl) from 30 s to 90 s,and increased the corrosion resistance of the Ni-P alloy coating as well.Namely,the Ni-P alloy coating prepared using the new plating process had zero corrosion loss as immersed in 5% NaCl solution for one year,much less than that of the Ni-P alloy coating prepared using conventional plating process which was 1.1 mg/cm2.