Investigation of the corroded surface of SiCw/Al composite

The change on the surface morphology of SiCw/Al composite during the early stage of corrosion in 3.5% NaCl solution has been observed by atomic force microscopy. The effect of interface (between whisker and matrix) and matrix on the corrosion process has been studied. The corrosion behavior of the SiCw/Al composite is summarized as: (1) the surface of the composite became rougher during corrosion, the average roughness of surface increased with the corrosion time; (2) pits preferentially formed at the end of whisker and propagated along the interface between whisker and matrix easily; (3) some of smooth peaks appeared on the corroded surface with the progression of corrosion, but they disappeared with increasing the corrosion time and the matrix became remarkably rougher.