PALLADIUM-NICKEL-PHOSPHORUS ALLOY ELECTROPLATING SOLUTION

• Main Authors: NAWAFUNE HIDEMI, MIZUMOTO SHOZO, HAGA MASAKI, OKADA TAKASHI
• Format: Patent
• Language: English
• Published: 24.04.1992
• Subjects: APPARATUS THEREFOR; CHEMISTRY; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; METALLURGY; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS

PURPOSE:To obtain an electroplating soln. giving a Pd-Ni-P alloy plating film contg. relieved stress, free from cracks and having satisfactory corrosion resistance by specifying the compsn. of an aq. soln. so that P is codeposited in a Pd-Ni alloy plating film. CONSTITUTION:This plating soln. is an aq. soln. contg. 0.01-0.5mol/l Pd compd., 0.01-1mol/l Ni compd., 0.02-1mol/l amine compd. and 0.001-0.5mol/l one or more kinds of P-contg. compds. selected among phosphorous acid and hypophosphorous acid compds. In the case of <0.01mol/l Pd compd., current efficiency is reduced and >0.5mol/l Pd compd. deteriorates the stability of the soln. without further increasing current efficiency. In the case of <0.01mol/l Ni compd., Ni codeposits hardly and >1mol/l Ni compd. deteriorates the stability of the soln. The amine compd. contributes toward stabilizing the soln. but >1mol/l amine compd. is uneconomical and <0.02mol/l amine compd. does not ensure stability. In the case of <0.001mol/l P-contg. compds., P codeposits hardly and >0.5mol/l P-contg. compds. deteriorate the appearance of a plating film.