Abstract: The present invention relates to a method for plating nickel onto metal substrates. The method broadly comprises the steps of passing the metal substrate to be plated through a dilute organic acid bath solution to remove contaminants and other deleterious materials, agitating the bath solution as the metal substrate passes therethrough, and thereafter electrolessly plating nickel on the surfaces of the metal substrate. The method of the present invention may be used to nickel plate substrates formed from steel, copper and aluminum.

Abstract: Method for preparing aluminum, especially large aluminum pieces or articles having a surface layer of aluminum oxide for subsequent metal plating wherein the aluminum or aluminum alloy substrate is immersed in a bath containing metal salts and acid such that the acid content relative to the metal salt is sufficient to remove the surface aluminum oxide layer without substantial attack on the underlying aluminum while enabling the permanent deposit thereon of a continuous, smooth, adherent metal or metal alloy coating directly onto the aluminum, thereby replacing the aluminum oxide layer. Subsequent, essentially blister-free electroless or electrolytic plating of nickel or a nickel alloy, copper or a copper alloy onto the metal or metal alloy coated aluminum are made possible thereby.