Dry sliding wear characteristics of Al-7Si-0.3Mg alloy with minor additions o f magnesium at high temperature

In this paper, effect of minor additions of magnesium content in the form of master alloys on the high-temperature dry sliding wear behaviour for A356 alloy has been reported. Alloy composition, normal pressures and sliding distances on A356 alloy at constant temperature of 300 C was studied. The cast alloys and worn surfaces were characterized by SEM/EDX microanalysis. The results indicate that the wear rate of A356 alloy increases with an increase in normal pressures and sliding distances in all the cases and decreases when 0.7% Mg is added to A356 alloy. The decrease in wear rate after the addition of Mg is mainly due to changes in microstructure which lead to improvement in mechanical properties. Further, worn surface study indicates that the formation of iron-rich oxide layer between the mating surfaces during sliding improves sliding wear performance. [GRAPHICS] .