第二相体积分数对Mg-13Gd-4Y-2Zn-0.5Zr合金力学性能的影响  

Effect of Second Phase Volume Fraction on Mechanical Properties of Mg-13Gd-4Y-2Zn-0.5Zr Alloy

作　　者：易明 杨亚琴[1] 张治民[1] YI Ming;YANG Yaqin;ZHANG Zhimin(School of Material Science and Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学材料科学与工程学院,山西太原030051

出　　处：《热加工工艺》2024年第10期68-71,77,共5页Hot Working Technology

基　　金：山西省自然科学基金项目(201801D121110)。

摘　　要：采用万能拉伸试验机、SEM、EDS及XRD对固溶处理后的Mg-13Gd-4Y-2Zn-0.5Zr合金力学性能、第二相形态、化学成分进行了分析,并利用Image-Pro-Plus软件对第二相体积分数进行了统计。结果表明:固溶处理后,合金中仍有大量不同形态、成分的第二相,主要是灰色块状LPSO相、灰色棒状LPSO相和白色点状富稀土相。随着固溶时间的增加,Mg-13Gd-4Y-2Zn-0.5Zr合金的抗拉强度与伸长率表现出先降低后升高的变化规律。在510℃固溶16 h,合金的抗拉强度与伸长率达到最小值,分别为196.77 MPa、3.8%。510℃固溶10~16 h,LPSO相体积分数不变,富稀土相体积分数增加,富稀土相质地较脆,受力时容易破碎,成为裂纹萌发和扩展的源头,使合金抗拉强度、伸长率均降低。510℃固溶16~19 h,富稀土相体积分数减少,合金的力学性能增加。The mechanical properties,the second phase morphology and composition of Mg-13Gd-4Y-2Zn-0.5Zr alloy after solid solution treatment were analyzed by universal tensile testing machine,SEM,EDS and XRD,and the second phase volume fraction was counted using Image-Pro-Plus software.The results show that after solid solution treatment,the alloy still has a large number of different forms and components of the second phase,mainly gray bulk LPSO phase,gray rod LPSO phase and white dot rich rare earth phase.With the increase of solution time,the change of tensile strength and elongation of Mg-13Gd-4Y-2Zn-0.5Zr alloy first decrease and then rise.Solution at 510℃for 16 h,the tensile strength and elongation of the alloy reaches the minimum of 196.77 MPa and 3.8%,respectively.Solution at 510℃for 10-16 h,LPSO phase volume fraction is unchanged,RE-rich phase volume fraction increases.The rare earth-rich phase is brittle in texture,and it is easy to break when stressing,which becomes the source of crack germination and propagation,which reduces the tensile strength and elongation of the alloy.Solution at 510℃for 16-19 h,the volume fraction of rare earth-rich phase decreases and the mechanical properties of the alloy increase.

关 键 词：Mg-13Gd-4Y-2Zn-0.5Zr合金 固溶时间 第二相 体积分数 力学性能 

分 类 号：TG166.4[金属学及工艺—热处理]