Corrosion resistance of Mg–5Al–xSr alloys

Four types of Mg–5Al alloy with various weight percentages of Sr ranging from 0 to 1.5 wt% were examined using electrochemical techniques and surface analyses. The electrochemical results indicated that the Mg–5Al alloy containing Sr to have a higher pitting potential and impedance than the Mg–5Al specimen with highest value being observed in the Mg–5Al–1Sr specimen. Sr addition induced the continuous precipitation of Al–Sr phases along with grain refinement and increased the formation of an Al(OH)3 film on the surface.