Innovative approach to protect magnesium powder during sintering

Abstract

Abstract Mg foams produced by powder metallurgy are considered as a new class of materials with unique properties. However, the high reactivity of Mg powder during sintering has a detrimental effect on their properties. The study aims at evaluating the possibility of using an insignificant amount of sulfur hexafluoride in the form of N2+0.2 %SF6 atmosphere for protecting EW62 Mg alloy during sintering at high temperature. The results obtained clearly demonstrate the relative advantage of N2+0.2 %SF6 as a protective atmosphere and cost effective environment compared to pure Ar. This was related to the active role of fluorine during sintering which improves the oxidation resistance of the Mg powder and consequently the properties of Mg foams in terms of structural integrity and strength.