Effect of Special Plating Films on Galvanic Corrosion Behavior between Metal and CFRTP

Abstract

In this study, electrochemical measurements and observations investigated galvanic corrosion behavior between various metals with or without projection-shaped Ni–Cu alloy plating film and carbon-fiber-reinforced thermoplastic (CFRTP) of corroded areas. Stainless steel, aluminum alloy, and CFRTP plates were prepared. Ni and Ni–Cu alloy electroplating were performed on the stainless steel plate. Electroless zinc plating, Ni, and Ni–Cu alloy electroplating were performed on the aluminum alloy plate. The galvanic current between the metal and CFRTP plates was measured using an electrochemical measurement system. The test solution was 0.06 mol/L NaCl aqueous solution. For Stainless steel/CFRTP, the galvanic current flow was negligible with and without the Ni–Cu alloy plating film. For aluminum alloy/CFRTP without the Ni–Cu alloy plating film, the galvanic current ranged from-80 to-120 μA/cm2 at a test temperature of 60°C. For aluminum alloy with the Ni–Cu alloy plating film, the galvanic current ranged from-60 to-80 μA/cm2. The galvanic current for the aluminum alloy plate with Ni–Cu alloy plating was lower than that of the aluminum alloy plate without Ni–Cu alloy plating film. The result suggests that the formation of the Ni–Cu alloy plating on the aluminum alloy improves corrosion resistance.