Influence of Processing Variables on the Corrosion Susceptibility of Metal-Matrix Composites

Abstract

Metal-matrix composites (MMC) suffer from preferential corrosion because of their nonhomogeneous composition and structure. In particular, aluminum alloy matrix materials are very susceptible to corrosion when the dispersoid is a noble phase, such as SiC. This paper describes the influence of processing variables on the corrosion susceptibility of aluminum metal-matrix composites. A high extrusion ratio and a modified solution heat treatment have been shown to enhance the corrosion resistance of a powder metallurgy (PM) AA(1) 7091 Al alloy (20 vol%) SiC (p = particulate) composite significantly.