Abstract: This paper presents an investigation on the microstructures and properties of the 17v.-% SiCw/Al-12Si composites.TEM observations and EDAX analysis revealed that Al diffuses into the SiC whiskers and that dislocations exist at the whisker/matrix interfaces. Tensile test results showed that the isothermal exposure and thermal cycle at both 573K and 733 K caused the UTS reduction of the composites,and the reduction in UTS due to thermal exposure at 733 K was much more significant than that due to thermal cycle at the same tem- perature.The SiC_W/Al-12Si composites were also found to have exellent wear resistance, which does not seem to vary much with the volume content of whiskers in the ronge of 11— 17%.

Key words: composites, SiC whisker, microstructure, strength