In this study, we developed a new kind of high-strength Mg–5.5Gd–3.5Nd–0.5Zn–0.4Zr (wt%) alloy. Microstructures and mechanical properties of this new kind of alloy under different heat treatment conditions have been investigated. The as-cast alloy was composed of α-Mg matrix, discontinuous α-Mg + Mg₅Gd eutectic phases, needle-like Mg₁₂Nd phases, spherical α(Zr) particles, and cuboid-shaped (Gd, Nd)H₂ phases within α-Mg grains. Rod-like Zn₂Zr₃ phases were formed and unevenly distributed inside the α-Mg matrix after solution treatment. Thin-plate β′ phases precipitated after aging at 205 °C for 24 h. The T6-treated alloy exhibited excellent tensile properties up to 250 °C. The dislocation cross-slip was activated when tensile temperature increased to 300 °C, which resulted in the largely decreased strength and increased elongation.

在本研究中，我们开发了一种新型高强度 Mg–5.5Gd–3.5Nd–0.5Zn–0.4Zr (wt%) 合金。研究了这种新型合金在不同热处理条件下的显微组织和力学性能。铸态合金由α-Mg基体、不连续的α-Mg+Mg ₅ Gd共晶相、针状Mg ₁₂ Nd相、球形α(Zr)颗粒和长方体(Gd,Nd)H ₂组成。 α-Mg 晶粒内的相。棒状 Zn ₂ Zr ₃固溶处理后，相在α-Mg基体内部形成且分布不均匀。在 205 °C 老化 24 h 后，薄板 β' 相析出。经 T6 处理的合金在高达 250 °C 时表现出优异的拉伸性能。当拉伸温度升高到 300 ℃时，位错交叉滑移被激活，导致强度大大降低，伸长率增加。