Simultaneously improved mechanical strength and corrosion resistance of Mg-Li-Al alloy by solid solution treatment

The mechanical property and corrosion resistance of as-cast Mg-10.1 wt% Li-4.8 wt% Al alloy subjected to solid solution treatment of 350 degrees C for 4 h (T4) were investigated. At room temperature, the ultimate tensile strength (127 MPa) of the as-cast sample was elevated to 250 MPa for the T4 sample. The corrosion resistance of T4 sample was also improved simultaneously, which was mainly ascribed to the combined effect of the absence of micro-galvanic couples and the protective surface film on the surface. The localized potential distribution confirmed that the micro-galvanic effect between anodic beta-Li and cathodic alpha-Mg accelerated the corrosion of ascast alloy.

Automated summary

Solid solution treatment significantly improves the tensile strength and corrosion resistance of Mg-Li-Al alloy. The enhanced corrosion resistance is mainly attributed to the combined effect of the absence of micro-galvanic couples and the protective surface film.