Study of heterostructure composition by regulating lamellar LPSO phase and the related strengthening mechanism in the Mg-Gd-Y-Zn-Zr alloy

作者：Shuangwu Xia, Ping Li, Junfu Dong, Tianle Wang, Liangwei Dai, Kemin Xue · 发表于：Journal of Magnesium and Alloys · 年份：2025 · DOI：10.1016/j.jma.2025.08.007 · 被引用次数：7 · 研究领域：Magnesium Alloys: Properties and Applications、Aluminum Alloys Composites Properties、Aluminum Alloy Microstructure Properties

• Three types of heterostructure with different composition were achieved in Mg-Gd-Y-Zn-Zr alloy by regulating lamellar 14H LPSO phase. The role of heterostructure with different composition on mechanical properties was systematically investigated. • The effect of 14H lamellar LPSO phase with different interspacing and thickness on dynamic recrystallization is illustrated in detail. • The related deformation mechanism was discussed and the activation of multiple slips is primarily affected by lamellar LPSO phase. • The sample with heterostructure composed of fine grains (volume fraction ∼67%), coarse grains (volume fraction ∼32.9%), block LPSO phase (volume fraction ∼11.5%), lamellar LPSO phase (volume fraction ∼18.6%) and granular LPSO phase (volume fraction ∼9.7%) exhibited high hetero-deformation induced strengthening and best combination of strength and ductility. The heterostructure preparation in Mg-rare earth (RE) alloy has attracted much attention due to the excellent enhancement of strength and ductility. However, the effect of heterostructure composition on mechanical properties in Mg-RE alloy is still not clear. In this work, three types of heterostructures with different composition induced by lamellar 14H long period stacking ordered (LPSO) phase were achieved in the Mg-Gd-Y-Zn-Zr alloys after cyclic extrusion and compression (CEC). The heterostructure was mainly composed of dynamic recrystallization (DRX) grains, deformed coarse grains, multiscale LPSO phase (bl...