Zn对Mg⁃11Gd⁃3Y⁃0.5Zr合金热压缩行为的影响  

Effect of Zn on Hot Compression Behavior of Mg⁃11Gd⁃3Y⁃0.5Zr Alloy

作　　者：王颂博 李全安[1,2] 陈晓亚 朱利敏[1] 张帅 关海昆[1] WANG Songbo;LI Quanan;CHEN Xiaoya;ZHU Limin;ZHANG Shuai;GUAN Haikun(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 740048,China)

机构地区：[1]河南科技大学材料科学与工程学院,洛阳471023 [2]有色金属共性技术河南省协同创新中心,洛阳471023 [3]西安理工大学材料科学与工程学院,西安740048

出　　处：《材料导报》2021年第4期4124-4128,共5页Materials Reports

基　　金：国家自然科学基金(51571084,51171059)。

摘　　要：本研究对均匀化后的Mg⁃11Gd⁃3Y⁃xZn⁃0.5Zr(x=0,0.3,0.7,1.5,质量分数/%)合金进行温度为350~500℃、应变速率为0.002~1 s-1的热压缩实验,对合金显微组织进行分析,计算了合金的热变形激活能,构建并分析了合金的热加工图。结果表明:Mg⁃11Gd⁃3Y⁃xZn⁃0.5Zr合金热变形发生了动态回复和动态再结晶,峰值应力都随Zn含量的增加而增大;流变应力随温度的升高或应变速率的降低而升高。在应变量小于0.4时,流变应力随Zn含量增加而增加,当应变量达到0.4后流变应力随Zn含量增加先增加后降低,在Zn含量为0.7%时流变应力达到最大值;少量Zn(0.3%)的加入就能明显提高合金的热变形激活能,但进一步增加Zn的含量(0.3%~1.5%)对合金激活能几乎没有影响;通过热加工图确定了合金适合的热加工工艺范围;Zn元素能够减小合金失稳区范围,减缓合金再结晶进程的同时细化了合金组织,当Zn含量为0.7%时合金的可热加工性最好。The homogenized Mg-11Gd-3Y-xZn-0.5Zr(x=0, 0.3, 0.7, 1.5, mass fraction/%) alloy was subjected to a hot compression experiment at temperature of 350-500 ℃ and strain rate of 0.002-1 s-1. The microstructure of the alloy was analyzed. The thermal deformation activation energy was established and the thermal processing map of the alloy was established and analyzed. The results showed that the thermal deformation and dynamic recrystallization of Mg-11 Gd-3 Y-xZn-0.5 Zr alloy occur. The peak stress increases with the increase of Zn content. The flow stress increases with the increase of temperature or decreases of strain rate. When the strain is less than 0.4, the flow stress increases with the increase of Zn content. When the strain reaches 0.4, the flow stress increases first and then decreases with the increase of Zn content. When the Zn content is 0.7%, the flow stress reaches the maximum value. The addition of Zn(0.3%) can significantly improve the thermal deformation activation energy of the alloy, but further increase the Zn(0.3%-1.5%) has little effect on the activation energy of the alloy. The hot working process range of the alloy is determined by the thermal processing map. Zn can reduce the range of instability zone, slow down the alloy recrystallization process and refine the alloy structure. When the Zn content is 0.7%, the hot working effect is the best.

关 键 词：Mg⁃11Gd⁃3Y⁃xZn⁃0.5Zr合金 热压缩 激活能 热加工图 

分 类 号：TG146.2[金属学及工艺—金属材料]