Microstructure, Corrosion and Electrochemical Properties of Cu/SiC Composites in 3.5 wt% NaCl Solution

This study investigated the role of SiC as a reinforcement on microstructure, corrosion, and electrochemical properties of Cu/xSiC (x = 0, 5, 10, 15, 20, 25, and 30 vol% SiC) composites. The powder metallurgy route was used to fabricate Cu/ SiC composite. The distribution of SiC reinforcing particles in the Cu matrix and their interfaces were investigated using optical and SEM/EDS microscopes. The various phases of Cu strengthened with SiC particles were detected using an X-ray diffractometer. The anticorrosion behavior and electrochemical properties of composites were investigated using various electrochemical techniques in 3.5 wt% NaCl solution. The electrochemical studies showed that the inclusion of SiC particles in the Cu matrix improved the resistance to corrosion. It was found that as the reinforcing particles increased to 20 vol%, the corrosion potential increased from - 240 to - 183 mV(Ag/AgCl), and the corrosion current density decreased from 5.01 to 0.02 mu A cm(-2), while the passive current density decreased from 17.58 to 4.74 x10(-4) A cm(-2). This behavior resulted from the nucleation and production of a good protective layer. On another side, increasing reinforcing particles over 20 vol%, the corrosion current density increased from 0.05 to 0.63 mu A cm(-2), while the corrosion potential shifted from - 196 to - 206 mV(Ag/AgCl).