Development of high strength Mg-Cu-Zn ultrafine eutectic composites with enhanced plasticity

Mg-Cu-Zn ultrafine eutectic composites with different length scale heterogeneity, consisting of micrometer size dendrites and/or ultrafine scale bimodal eutectics, exhibit high yield strength as well as good plasticity at room temperature compression. Among these alloys, micron-scale α-Mg dendrites reinforced ultrafine eutectic composites exhibit high yield strength of 310 ̃ 420 MPa and large plasticity of 7 ̃ 12%. Meanwhile, a Mg ₇₂Cu₅Zn₂₃ alloy comprising a bimodal eutectic structure without the micron-scale α-Mg dendrites shows the optimized mechanical properties the highest yield strength of 455 MPa combined with a considerable plastic strain of ̃5%.