It is challenging to develop Mg alloys with high strength-ductility synergy and isotropic mechanical properties. An industrial-scale ultrafine-grained (UFG) Mg-10.6Gd-2Ag wt. % alloy with excellent strength-ductility synergy and near-isotropic mechanical behavior was made by an industrial-scale rotary die equal channel angular pressing (RD-ECAP). The microstructure of the UFG alloy involves the primarily submicron α-Mg grains with an average grain size of 760.5 nm and the high-density submicron β phase (Mg₅Gd) precipitates (267.8 nm). Room temperature tensile tests results reveal that the UFG alloy exhibits an over three times tensile yield strength, near two times ultimate tensile strength, and more than one and a half times elongation along three orthogonal test directions than the as-cast Mg alloy. The improvement of strength is linked to the effect of the grain boundary strengthening as well as the precipitation strengthening. The enhanced ductility is ascribed to the ultrafine grains with low dislocation density, which provide a degree of dislocation storage capacity and facilitates multiple potential deformation modes. The near-isotropic mechanical behavior stems from the weak texture and multiple deformation modes.

开发具有高强度-延展性协同作用和各向同性机械性能的镁合金具有挑战性。工业规模的超细颗粒（UFG）Mg-10.6Gd-2Ag wt。通过工业规模的旋转模等通道转角挤压（RD-ECAP）制成了具有优异的强度-延展性协同作用和接近各向同性的机械性能的％合金。UFG合金的微观结构主要包括平均粒径为760.5 nm的主要亚微米α - Mg晶粒和高密度亚微米β相（Mg ₅Gd）沉淀（267.8 nm）。室温拉伸试验结果表明，与铸态Mg合金相比，UFG合金的拉伸屈服强度高三倍，极限拉伸强度接近两倍，在三个正交试验方向上的延伸率是其一半以上。强度的提高与晶界强化和沉淀强化的效果有关。具有较低位错密度的超细晶粒可提高延展性，从而提供一定程度的位错储存能力并促进多种潜在的变形模式。近乎各向同性的机械行为源于薄弱的织构和多种变形模式。