Tribo-metallurgical behaviour of high Zn content Al-Zn-Mg-Cu alloy in different homogenization conditions

A significant constraint of aluminum alloys in aircraft and automobile industrial applications is their poor mechanical properties as well as low tribological behavior. In the present study, the correlation between microstructure, hardness, and wear behavior of high Zn (10 wt.%) alloys containing Al-Zn-Mg-Cu was studied. Homogenization treatment at 450°C in the range of 0 to 40 h, followed by an aging process at 120°C/24 h, was applied to the alloy samples. The results show that the alloy homogenized for 16 h exhibits peak hardness due to the presence of precipitates at the grain boundary region as well as in the matrix, which act as intense points for pinning in the Al-matrix to slow the dislocation movement. The wear behavior of the alloy was investigated by a dry sliding wear test. Worn surfaces were investigated to identify the wear mechanism. Archard’s and Fleischer’s wear models were analyzed to correlate with the wear test results of the alloy during homogenization time.