WEAR-RESISTANCE OF AL-SI ALLOYS AND ALUMINUM MATRIX COMPOSITES

The wear resistance for hypereutectic Al-Si, 6061, 4032 alloys reinforced with Al2O3 fibers, SiC particulates, SiC whiskers, C fibers and Pb particulates has been investigated. The wear loss for hypereutectic Al-Si alloys is observed to be inversely proportional to the size and directly proportional to the spacing of Si particles and the counter material surface roughness. The effect of SiC whisker on wear resistance for Al-Si alloys is found to be a superimposing of the direct contribution of SiC whisker on the secondary effect on pinning the slip of Si particles. The composites reinforced with a hybrid of SiC whisker, SiC particulate and C fiber exhibit excellent wear resistance. SiC whisker is found to be a barrier against slip of relatively large reinforcements.