Electrochemical behavior of diamond-reinforced composites

A diamond-reinforced 1100 aluminum matrix composite (DRC) containing 15% by volume of 30 μm diamond particles was fabricated using standard powder metallurgy techniques at 600 °C. A temperature higher than that required solely for composite consolidation was selected to investigate whether carbide formation occurred. Scanning electron micrographs and Raman spectroscopy showed no detectable amount of carbide formation. Electrochemical testing showed that the pitting potential of the composite was the same as that of the pure matrix material, which also indicates that either carbides did not form or the amount formed was so small as not to alter the breakdown potential of the DRC.