摘要
采用光学显微镜、X射线衍射仪、扫描电镜对时效态Mg-4Y-2Sm-xGd-0.5Zr(x=0, 0.5, 1, 1.5 mass%)合金进行了微观组织及物相分析,并采用拉伸实验机在室温至250℃下对其进行了力学性能测试。结果表明:时效态Mg-4Y-2Sm-0.5Zr合金组织主要由α-Mg基体与Mg24Y5和Mg41Sm5析出相组成;加入Gd元素后,合金组织中有新相Mg5Gd形成;随着Gd添加量的增加,Mg5Gd析出相的数量增加,合金的晶粒得到细化;同一温度拉伸时,合金的抗拉强度在Gd添加量为1.0 mass%时达到峰值,其中室温拉伸时含1.0 mass%Gd的合金的抗拉强度为223.6 MPa;同一成分合金的抗拉强度随着拉伸温度的升高呈逐渐降低的趋势;室温拉伸时合金的伸长率在Gd添加量为0.5 mass%时最高,为15.13%;在150~250℃时高温拉伸时,伸长率在Gd添加量为1.0 mass%时达到峰值,并且比较稳定;加入Gd元素后的合金在150~250℃时具有良好的耐高温性能和热稳定性。
Microstructure and phases of aged Mg-4Y-2Sm-xGd-0.5Zr(x=0, 0.5, 1, 1.5 mass%) alloys were analyzed by means of optical microscope, X-ray diffractometer and scanning electron microscopy, and mechanical properties of the alloys were tested by tensile testing machine at room temperature to 250 ℃. The results show that the microstructure of the aged Mg-4Y-2Sm-0.5Zr alloy is mainly composed of α-Mg matrix and Mg24Y5 and Mg41Sm5 precipitated phases. After the addition of Gd, the new phase Mg5Gd is formed in the alloys. With the increase of Gd content, the amount of the precipitated phase of Mg5Gd increases and the grain size of the alloys is refined. At the same tensile temperature, the tensile strength of the alloys reaches the peak value when the Gd content is 1.0 mass%, and the tensile strength of the alloy with 1.0 mass% Gd is 223.6 MPa at room temperature. The tensile strength of the alloys with same composition decreases gradually with the increase of the tensile temperature. At room temperature, the elongation of the alloy is up to 15.13% when the Gd content is 0.5 mass%. At 150-250 ℃, the elongation of the alloy reaches the peak value when the Gd content is 1.0 mass%, and it is relatively stable. The alloys added with the Gd element have good high temperature resistance and thermal stability at 150-250 ℃.
作者
李志涛
李全安
陈晓亚
LI Zhi-tao;LI Quan-an;CHEN Xiao-ya(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,China;Collaborative Innovation Center of Nonferrous Metals,Henan Province,Luoyang 471023,China;School of Materials Science and Engineering,Xi'an University of Technology,Xi'an 710048,China)
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2019年第12期25-31,共7页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金(51571084,51171059)
