Wear characteristics of Al-Al₂O₃ composites produced by powder metallurgy process

Abstract

Wear characteristics of Al-base composites containing 5 to 20 vol % Al₂O₃ have been investigated and compared with those of commercial purity aluminium used a matrix phase and a commercial 7010 grade Al-alloy. All the materials have been synthesized by powder metallurgy method using hot compaction and hot extrusion processes and wear testing has been carried out in dry sliding condition using a pin-on-disc type machine. The wear rate of composites is observed to be lower than that of the aluminium compacts but higher than the commercial grade alloy. An increase Al₂O₃ led to decrease in wear rate of composites, under the applied load of 5 to 35 N and sliding velocity from 0.25 to 1.5 ms^-1. The possible reasons for this behaviour are discussed in light of the microstructure of the alloy and nature of the worn surfaces of the specimens.