High temperature wear behaviour of Al-4Cu-TiB₂in situ composites

Abstract

The effect of sliding temperature and load on the wear behavior of Al-4Cu alloy and Al-4Cu-TiB₂in situ composites was studied in this paper. The wear resistance of the Al-4Cu alloy increased with increase in wt.% of reinforcement TiB₂ particles at all temperatures and loads. The transition in the wear mode from mild to severe wear was strongly influenced by the addition of TiB₂ particles. The Al-4Cu alloy showed a transition from mild to severe wear at a load of 80 N and at a sliding temperature of 100 °C. But with the addition of 5 and 10 wt.% of in situ TiB₂ particles to the Al-4Cu matrix, the transition temperatures are increased to 200 and 300 °C and the loads are increased to 100 and 120 N, respectively. Analysis of wear surfaces by scanning electron microscopy revealed the transition in wear mode. It was observed that at elevated temperature the predominant wear mechanisms for the Al-4Cu alloys are adhesion and metal flow, whereas for Al-4Cu-TiB₂ composites oxidation, delamination and metal flow are the most dominant wear mechanisms.