A method for the chemical activation of nickel surface as a pretreatment by a helicoidal guide for the electrolytic or electroless metal deposition

摘要

Process for the chemical activation of the surface of a body consisting of nickel or a Ni alloy, as a pretreatment before electroplating or electroless plating, esp. the deposition of Ni using an activating soln. The activation soln. is an acid mixt. of, by vol. (a) 5-15% H2SO4 (98%) with (b) 5-15% ortho-phosphoric acid (89%), (c) 25-35% NHO3 (65%) and (d) 40-60% acetic acid (99%). The pref. mixt. contains 10% (a); 10% (b); 30% (c) and 50% (d); it may also contain 0.1 g/l PdCl2 or 0.1 g/l AgNO3. The pref. working temp. is 20-90 degrees C., esp. room temp., for 5-30 seconds, esp. 10 seconds. Method removes passive layers on nickel prior to coating.