Effect of T6 heat treatment on corrosion resistance and mechanical properties of AM50 magnesium alloy

摘要

To improve the corrosion resistance and mechanical properties of AM50 magnesium alloy, T6 heattreatment was applied. The microstructure, mechanical properties and corrosion properties of ascast and T6 heat-treated alloy were studied. The results indicated that theβphase presented at thegrain boundaries along with Al–Mn phase after T6 heat-treatment. Because of solid solution andaging treatments, the tensile strength of the AM50 magnesium alloy was increased. Thedecreasing of theβphase owing to the solidsolution during T6 treatment, which causes Al solidsolution in theα-Mg phase, and it is favourable for increasing the corrosion resistance of AM50magnesium alloy. The fracture mechanisms of the as-cast and T6 heat-treated alloy were quasicleavage fracture. The corrosion residual strength of the T6 heat-treated alloy was higher thanthat of the as-cast alloy. Compared with the as-cast alloy, the corrosion rate of the T6 heattreated alloy decreased gradually.