Zn和Gd元素含量和比例对铸态和挤压态Mg-8Li合金显微组织和力学性能的影响  

Effects of Zn and Gd contents and their ratios on microstructure and mechanical properties of as-cast and as-extruded Mg−8Li alloys

作　　者：黄玉川 张泉达 欧阳思杰 孙福臻 孙家伟 李蕙宇 吴国华[3] 陈培军 刘文才[3] Yu-chuan HUANG;Quan-da ZHANG;Si-jie OUYANG;Fu-zhen SUN;Jia-wei SUN;Hui-yu LI;Guo-hua WU;Pei-jun CHEN;Wen-cai LIU(State Key Laboratory of Advanced Forming Technology and Equipment,China Academy of Machinery Science and Technology Group Co.,Ltd.,Beijing 100083,China;Beijing National Innovation Institute of Lightweight Ltd.,Beijing 100083,China;National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Luoyang Shengya Magnesium Alloy Technology Co.,Ltd.,Luoyang 471921,China)

机构地区：[1]中国机械科学研究总院集团有限公司,先进成形技术与装备国家重点实验室,北京100083 [2]北京机科国创轻量化科学研究院有限公司,北京100083 [3]上海交通大学,材料科学与工程学院,轻合金精密成型国家工程中心和金属基复合材料重点实验室,上海200240 [4]洛阳晟雅镁合金科技有限公司,洛阳471921

出　　处：《Transactions of Nonferrous Metals Society of China》2024年第3期798-811,共14页中国有色金属学报（英文版）

基　　金：supported by the Open Fund of State Key Laboratory of Advanced Forming Technology and Equipment (No. SKL202005);the Major Scientific and Technological Innovation Project of Luoyang,China(No. 2201029A);the National Natural Science Foundation of China (Nos. 51771115, 51775334);the Research Program of SAST-SJTU Joint Research Center of Advanced Spaceflight Technologies,China (No. USCAST2020-14)。

摘　　要：研究Zn和Gd元素含量及其质量比对铸态和挤压态Mg-8Li合金显微组织和力学性能的影响。挤压后,析出相破碎。β-Li中分散着粒径约100 nm的球形微粒。形成了由长条状α-Mg粗晶和再结晶β-Li细晶组成的双峰结构。挤压后合金的强度和塑性显著提高,且屈服强度和极限抗拉强度随Zn和Gd含量的增加而增加。Mg-8Li-8Zn-2Gd合金表现出最优的综合性能,其屈服强度、极限抗拉强度和伸长率分别为274 MPa、283 MPa和39.9%。挤压态合金主要强化机制为由β-Li的细晶强化和α-Mg的织构强化组成的双模态结构强化和析出相的弥散强化。The effects of contents of Zn and Gd elements and their mass ratios on microstructure and mechanical properties of as-cast and as-extruded Mg-8Li alloys were investigated.After extrusion,the precipitates are broken,and fine spherical particles with size about 100 nm are found to disperse in theβ-Li.The bi-modal structure consisting of long-strip-like coarse-grainα-Mg and recrystallized fine-grainβ-Li is formed.The strength and plasticity of the alloys are greatly improved after extrusion,and the YS and UTS increase with the increase of Zn and Gd contents.The Mg-8Li-8Zn-2Gd alloy exhibits an optimum comprehensive performance with the YS of 274 MPa,UTS of 283 MPa,and EL of 39.9%.The bi-modal structure strengthening consisting of the fine crystal strengthening ofβ-Li and texture strengthening ofα-Mg,and the dispersion strengthening of precipitations are the main strengthening mechanisms.

关 键 词：镁锂合金 挤压变形 双峰结构 弥散强化 

分 类 号：TG146.22[一般工业技术—材料科学与工程]