Effect of Bi alloying and cold rolling on microstructure and mechanical properties of LA141 Mg-Li alloy

LA141-xBi (x = 0, 1, 2, 3) alloys were prepared, and the effects of Bi alloying and cold rolling on the microstructure and mechanical properties were investigated. The results indicate that, with the addition of Bi, the grains were refined, and Mg3Bi2 phase is formed in the alloys. The as-cast LA141-2Bi possesses the tensile strength of 174 MPa, 21% higher than that of LA141 alloy. The cold rolled LA141-2Bi alloy exhibits a good balance between strength and plasticity, with a tensile strength of 237 MPa and an elongation of 30.5%. This improvement is primarily attributed to grain refinement, the dispersion of second-phase particles, high-density dislocations, and the presence of nano-twins.