Role of magnesium and minor zirconium on the wear behavior of 5xxx series aluminum alloys under different environments

Abstract

The tribological performance of 5xxx series aluminum alloys with ternary zirconium is evaluated at ambient conditions under dry, wet and saline environment. The experiment has been done using a Pin-on-Disk apparatus under an applied load of 20N. The sliding distances varies ranging from 116m-2772m at a sliding velocity of 0.385 ms-1. The results show that presence of Mg and Zr into this alloy helps to increase their strength and wear resistance under dry sliding condition. But they significantly suffer under wet and corrosive environment due to formation of β-phase Al3Mg2, to slip bands and grain boundaries which may lead to and stress-corrosion cracking. The variation of friction coefficient is observed in wet and corrosive environment due to the formation of oxidation film, lubrication, and corrosion action in solution. The SEM fracture surface shows that brittle Al3Mg2 phase initiate the brittle fracture surface for Al-Mg alloy and Zr addition accelerate the brittleness of the alloy owing the fine precipitates of Al3Zr.