压缩与半固态等温热处理对Mg-3Al-0.8Gd合金组织与性能的影响  

Effect of Compression and Semi-solid Isothermal Heat Treatment on Microstructure and Properties of Mg-3Al-0.8Gd Alloy

作　　者：薛海涛 李小妮[2] 杜威 杨朔 XUE Haitao;LI Xiaoni;DU Wei;YANG Shuo(Institute of Physical Education,Xianyang Normal University,Xianyang 712000,China;Engineering College,Xi'an University,Xi'an 710065,China;College of Materials,Xi'an Jiaotong University,Xi'an 710049,China;College of Materials,Shenyang University of Technology,Shenyang 110870,China)

机构地区：[1]咸阳师范学院体育学院,咸阳712000 [2]西安文理学院工程学院,西安710065 [3]西安交通大学材料学院,西安710049 [4]沈阳工业大学材料学院,沈阳110870

出　　处：《机械工程材料》2020年第5期33-37,43,共6页Materials For Mechanical Engineering

基　　金：陕西省教育厅专项科学研究项目(17JK1112);咸阳师范学院校级课题资助项目(XSYK18028)。

摘　　要：对Mg-3Al-0.8Gd合金进行了压缩变形及半固态等温热处理,研究了压缩变形量(10%,15%,20%)、等温温度(530,540,550,560,570℃)及保温时间(3,5,10,15min)对该合金显微组织与硬度的影响,并对比了铸态和热处理态Mg-3Al-0.8Gd合金的拉伸和冲击性能。结果表明:不同条件压缩变形及等温热处理后,Mg-3Al-0.8Gd合金组织均由α-Mg基体和β-Mg17Al12相组成;随着等温温度、保温时间及压缩变形量的增加,合金中的α枝晶逐渐转变为等轴晶,晶粒细化,组织均匀性提高,同时显微硬度增大;压缩变形20%并经550℃保温15 min热处理后,Mg-3Al-0.8Gd合金的抗拉强度、断后伸长率、断面收缩率和冲击吸收能量较其铸态合金的分别提高了11.3%,32.6%,3.8%和23.3%。Compression deformation and semi-solid isothermal heat treatment of Mg-3 Al-0.8 Gd alloy were carried out.The effects of the compression deformation(10%,15%,20%),isothermal temperature(530,540,550,560,570℃)and holding time(3,5,10,15 min)on the microstructure and hardness of the alloy were studied.The tensile and impact properties of as-cast and heat-treated Mg-3 Al-0.8 Gd alloys were compared.The results show that the microstructures of Mg-3 Al-0.8 Gd alloy after compression deformation and isothermal heat treatment under different conditions were all composed of α-Mg matrix and β-Mg17Al12 phase.With the increase of compression deformation,isothermal temperature and holding time,theαdendrites were gradually transformed into equiaxed grains,the grains were refined,the structure uniformity was improved,and the microhardness increased.The tensile strength,elongation after fracture,section shrinkage and shock absorption energy of Mg-3 Al-0.8 Gd alloy with compression deformation of 20% after isothermal treatment at 550℃ for 15 min were 11.3%,32.6%,3.8%and 23.3% higher than those of the as-cast alloy,respectively.

关 键 词：等温热处理 Mg-Al-Gd合金 显微组织 拉伸性能 抗冲击性能 

分 类 号：TG146[一般工业技术—材料科学与工程]