Tribological behaviour of aluminium-zinc-magnesium alloy processed by equal channel angular pressing

Abstract

In the present work, tribological behaviour of the Al-5Zn-2 Mg alloy processed by equal channel angular pressing (ECAP) was studied. Initially, the alloy was prepared by die casting process. ECAP processing was carried out in a split die with an angle of 120° between two channels. ECAP processing was carried out at 150 °C in route B<inf>C</inf> upto four passes. After ECAP, noticeable decrease in the grain size was observed which leads to significant increase in the hardness and strength of the alloy. In homogenized condition, grain size of 180 mm was observed. While after four passes, grain size was reduced to 1-2 mm. After ECAP, the hardness and strength of the alloy was increased by 122% and 135%, respectively from the initial condition. Predominantly, after ECAP, noticeable decrease in the wear volume loss and coefficient friction of the material was observed. To understand the effect of ECAP on the tribological behaviour of the alloy; worn surfaces of the wear test samples were studied by using scanning electron microscope. © 2020 Elsevier Ltd. All rights reserved.