Mg-10Gd-4.8Y-0.6Zr铸态合金经525℃、16 h均匀化退火后，在500℃轧制成总变形量为84%的板材，轧制后在200℃进行时效处理。观察合金的微观组织变化，并测试合金的力学性能。结果表明：轧制变形明显细化了晶粒尺寸，轧制后组织中存在方块相和长条状相；轧制初期组织中存在大量孪晶，孪晶能很好地协调塑性变形，并诱发了孪生动态再结晶；随着轧制变形量的增大，孪晶数量减少，再结晶方式以晶界弓出形核为主。轧制T5态合金具有优异的高温力学性能，200、250、300和350℃时抗拉强度分别为392、381、251和112 MPa，350℃拉伸时伸长率达到107.0%。%The as-cast Mg-10Gd-4.8Y-0.6Zr alloy sheets were rolled at 500 ℃ with 84% total reduction after being homogenized at 525 ℃ for 16 h and then aged at 200 ℃. The microstructures and mechanical properties were investigated. The results show that the grain size can be effectively refined by rolling process, cuboid-shaped phases and strip-shaped phases exist after being rolled. A mass of twins exist after initially being rolled, they can harmonize the plastic deformation and cause twinning-induced DRX. The number of twins decreases with the increase of rolling reduction and the DRX mode turns into grain boundary bulging mechanism. The rolled-T5 alloy has excellent elevated temperature mechanical properties: the tensile strength at 200, 250, 300 and 350 ℃ are 392, 381, 251 and 112 MPa, respectively, and the elongation at 350℃can reach 107.0%.
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