Room temperature strengthening and quasi-superplasticity behavior in superlight Mg-3.11Li-2.31Al-1.95Sn-0.94Y-0.45Er alloy processed by multidirectional forging and asymmetric rolling  

多向锻造异步轧制制备超轻Mg-3.11Li-2.31Al-1.95Sn-0.94Y-0.45Er合金的室温强化与准超塑性行为

作　　者：Fu-rong CAO Nan-pan GUO Pan-ning XU Guang-ming XU 曹富荣;郭楠盼;徐潘宁;许光明(东北大学材料科学与工程学院,沈阳110819;东北大学轧制与连轧自动化国家重点实验室,沈阳110819)

机构地区：[1]School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China [2]State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China

出　　处：《Transactions of Nonferrous Metals Society of China》2025年第3期800-818,共19页中国有色金属学报(英文版)

基　　金：supported by the National Natural Science Foundation of China(No.51334006)。

摘　　要：To explore ambient strengthening and high temperature ductility,a combined forming approach of multidirectional forging and asymmetric rolling was proposed.A novel multicomponent ultralight Mg-3.11Li-2.31Al-1.95Sn-0.94Y-0.45Er alloy was fabricated.The microstructural evolution and mechanical properties were investigated by microstructural characterization and tensile test.The combined forming results in remarkable grain refinement.The ultimate tensile strength and elongation of(255±7)MPa and 24.9%,respectively,were obtained at room temperature.The contribution of various strengthening mechanisms of the rolled alloy was obtained.Microstructural examination revealed the occurrence of dynamic recrystallization at 473-573 K and dynamic grain growth at 573-623 K.The maximum elongation of 293.9% was demonstrated at 623 K and 5×10^(-4) s^(-1).The dominate deformation mechanism at elevated temperatures is dislocation viscous glide.为了探索镁锂合金的室温强化与高温塑性,提出一种多向锻造与异步轧制组合成形方法。采用该方法制备了新型多元超轻Mg-3.11Li-2.31Al-1.95Sn-0.94Y-0.45Er合金。采用显微组织表征和拉伸测试研究了合金的显微组织与力学性能。经过该组合成形,合金发生显著晶粒细化。室温获得的极限抗拉强度与伸长率分别为(255±7)MPa与24.9%。获得了轧制合金各种强化机理的贡献。显微组织观察发现,合金在473~573 K发生动态再结晶,在573~623 K发生动态晶粒生长。在623 K和5×10^(-4)s^(-1)条件下获得了293.9%的最大伸长率。主导合金高温变形的机理为位错黏性滑移。

关 键 词：Mg−Li−Al alloy multidirectional forging asymmetric rolling microstructure strengthening super-plasticity 

分 类 号：TG1[金属学及工艺—金属学]