Twin evolution in cast Mg-Gd-Y alloys and its dependence on aging heat treatment
铸造 Mg-Gd-Y 合金的双重演变及其对时效热处理的依赖
鋳造Mg-Gd-Y合金の双晶の進化と時効熱処理への依存
주조 Mg-Gd-Y 합금의 트윈 진화와 시효 열처리에 대한 의존성
Evolución gemela en aleaciones de Mg-Gd-Y fundidas y su dependencia del tratamiento térmico de envejecimiento
Double évolution des alliages coulés Mg-Gd-Y et sa dépendance au traitement thermique de vieillissement
Эволюция двойников в литых сплавах Mg-Gd-Y и ее зависимость от термической обработки старением
Jingli Li ¹, Zhaohui Dong ¹, Xin Yi 易新 ¹, Di Wu 吴迪 ², Rongshi Chen 陈荣石 ²
¹ Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871, China
中国 北京 北京大学工学院力学与工程科学系
² Shi-Changxu Innovation Center for Advanced Materials, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
中国 沈阳 中国科学院金属研究所师昌绪先进材料创新中心
Effects of rare-earth (RE) and precipitates on twin evolution in cast Mg-10Gd-3Y-0.5Zr (wt.%) (GW103) alloys of solid solution (T4) and aged (T6) states are investigated performing quasi-static room temperature compression tests and microstructural characterization. It is found that both {10–12} and {11–21} extension twins (ET1 and ET2) can appear in the T4 and T6 states but with different emergence sequences.
As the aging heat treatment leads to consumption of RE solutes which could inhibit atomic shuffling required for nucleation of ET1 but not ET2, ET2 occurs prior to ET1 in the T4 state, and ET1 emerges before ET2 in the T6 state. The extension twins here mainly coordinate the plastic deformation through the non-Schmid effect. Our results shed light on the influence of RE elements on twin evolution in magnesium alloys and have implications in developing high-performance Mg-RE alloys.
