A High Strength-Ductility Balanced Mg-1Ca-0.5Mn-0.53Ce Mg Alloy Sheet by Multi-pass Low-Temperature Rolling

We elucidate here the influence of the rolling process on the microstructure and tensile properties of Mg-1Ca-0.5Mn-0.53Ce alloy. Intriguingly, the alloy subjected to 5-pass low-temperature rolling exhibited an excellent strength-ductility balance (ultimate tensile strength (UTS) = 261.4 MPa and elongation (EL) = 20%), which was far better than the one subjected to 4-pass low-temperature rolling (UTS = 218.3 MPa and EL = 4.3%). The coarse Mg2Ca particles in the 4-pass sample led to the local stress concentration, with consequent initiation of micro-cracks at the early deformation stage. In contrast, the microstructure of the 5-pass sample characterized by homogeneous ultra-fine grain, double peak texture, and refined precipitates contributed to the superior tensile properties.