Aiming at the low cost of rare-earth magnesium alloys under industrial production conditions

combining with the principle of total solute control and rare earth coupling strengthening

Mg-Y-Gd-Sm series casting magnesium alloys were designed. Combining with the DSC curve and the as-cast structure

the proportion of divorced eutectic phases in the alloys was analyzed. Meanwhile

the structure and mechanical properties of the alloys after solution treatment with different processes and the age hardening curves at different temperatures were analyzed comparatively to optimize the solution and age heat treatment process. The results show that the mechanical properties of the Mg-4.5 Y-2.5 Gd-1.5 Sm alloy prepared by the sand mold under the slow cooling condition are relatively desirable after the T6 heat treatment at 530 ℃×24 h+200 ℃×100 h

where the tensile strength

yield strength and elongation reach 267 MPa

200 MPa

2.0%

respectively.