Microstructure and mechanical properties of Mg-9Li-3Al-xGd alloys

The influence of gadolinium on the microstructure and mechanical properties of Mg-9Li-3Al alloy was investigated. Results show that the addition of Gd can effectively refine the alpha-Mg phase and change the morphology of the alpha-Mg phase. Meanwhile, the Al3Gd phase is mainly distributed at the boundaries of the alpha-Mg phase and inside the alpha-Mg phase. The mechanical property tests reveal that the addition of Gd can effectively improve the mechanical properties of the as cast alloys. When the content of Gd is 2.0%, the tensile strength and yield stress (engineering stress) reach max values of 188 and 174 MPa respectively. When the content of Gd addition is 2.5%, the elongation of the alloy is 15.7%.