挤压铸造对高锌镁合金组织与力学性能的影响  

Effects of Squeeze Casting on the Microstructure and Mechanical Properties of High Zinc Magnesium Alloy

作　　者：王杰 周吉学 唐守秋 高恩志 Wang Jie;Zhou Jixue;Tang Shouqiu;Gao Enzhi(School of Materials Science and Engineering,Shenyang Aerospace University;Shandong Provincial Key Laboratory of High Strength Lightweight Metallic Materials,Qilu University of Technology(Shandong Academy of Sciences))

机构地区：[1]沈阳航空航天大学材料科学与工程学院,沈阳110136 [2]齐鲁工业大学(山东省科学院)新材料研究所

出　　处：《特种铸造及有色合金》2020年第10期1062-1066,共5页Special Casting & Nonferrous Alloys

基　　金：辽宁省教育厅一般项目资助项目(L2015410,JYT19064)

摘　　要：以高锌Mg-14Zn-3Al镁合金为研究对象,利用OM、XRD和SEM等研究了挤压铸造工艺对Mg-14Zn-3Al镁合金的显微组织、铸造缺陷和力学性能的影响。结果表明,挤压铸造Mg-14Zn-3Al合金的显微组织由α-Mg基体、长块状τ-Mg_(32)(Al,Zn)_(49)相、颗粒状或骨骼状的ε-MgZn相组成。随着挤压铸造压力不断增加,合金组织得到细化,第二相的数量增多,显微缩松得到抑制,铸件中的缩松面积从15.67%急剧减少到0.81%。经过挤压铸造处理后,Mg-14Zn-3Al合金的抗拉强度、伸长率分别达到218.1 MPa、5.2%,合金的力学性能得到明显改善。The influence of squeeze casting on the microstructure,casting defects and mechanical properties of Mg-14Zn-3Al was investigated by OM,XRD and SEM.The results show that the microstructure of as-squeezed Mg-14Zn-3Al alloy is composed ofα-Mg matrix,long blockτ-Mg_(32)(Al,Zn)_(49)phase and granular or skeleton-likeε-MgZn phase.With the increase of the squeeze pressure,the microstructure of the alloy is refined and the quantity of the second phase is increased.Meanwhile,the casting defects in the alloy are inhibited,whose area fraction in the casting is sharply reduced from 15.67%to 0.81%.After squeeze casting treatment,the tensile strength and elongation of Mg-14Zn-3Al alloy can reach 218.1 MPa and 5.2%,respectively,which are much higher than those of gravity casting(192.6 MPa,1.2%).

关 键 词：MG-ZN-AL合金 挤压铸造 微观组织 缩松缺陷 力学性能 

分 类 号：TG249.2[金属学及工艺—铸造] TG146.22[一般工业技术—材料科学与工程]