氩气处理对AZ91镁合金高温力学性能的影响  

Effects of Ar Dehydrogenation on Mechanical Properties of AZ91 Alloy at High Temperature

作　　者：赵正任 贾征[1,2] 王彤 高源 郭锦鹏 胡天润 柳鑫 Zhao Zhengren;Jia Zheng;Wang Tong;Gao Yuan;Guo Jin peng;Hu Tian run;Liu Xin(College of Mechanical Engineering,Shenyang University;Key Laboratory of Electromagnetic Processing of Materials,Ministry of Education,Northeastern University)

机构地区：[1]沈阳大学机械工程学院 [2]东北大学材料电磁过程研究教育部重点实验室

出　　处：《特种铸造及有色合金》2020年第4期445-448,共4页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(51901037);辽宁省自然科学基金指导计划资助项目(2019-ZD-0561);辽宁省博士启动基金资助项目(2019-BS-083);2019年沈阳大学大学生创新创业训练计划资助项目(2019110350102).

摘　　要：研究了氩气处理对AZ91镁合金高温力学性能的影响。结果表明,经过氩气处理后,每100g熔体中的氢含量从未处理的14.8cm^3降低至7.3cm^3,除气率高达50.7%;在20、100、175、250、325和400℃对合金分别进行拉伸试验,发现除气对合金抗拉强度和屈服强度的影响随温度升高而逐渐减小,但对伸长率的影响正好相反。在温度低于250℃时除气,合金强度显著提高,伸长率变化不明显,除气对在高温(250~325℃)拉伸时强度影响不大,但明显提高了镁合金的伸长率,另外,应变硬化指数(n)值相差不大(分别为0.04和0.03)。Effects of Ar dehydrogenation on mechanical properties of AZ91 alloy at high temperature were investigated.The results indicate that the hydrogen content can be reduced from 14.8 cm^3/100 g to 7.3 cm^3/100 g and the degassing efficiency reaches to 50.7%.The effects of degassing on tensile and yield strength of the alloy are decreased with the increase in temperature in AZ91 alloy at 20,100,175,250,325 and 400 ℃,respectively,while that on elongation is opposite to that on strength.The strength of AZ91 alloy after degassing is improved obviously when the temperature is lower than 250 ℃ with little difference on elongation.Degassing has little effect on strength of alloy at the temperature from 250℃to 325℃.However,the elongation of alloy is improved obviously and the strain hardening exponents are basically the same(0.04 and 0.03,respectively).

关 键 词：AZ91镁合金 除气 高温力学性能 应变硬化指数 

分 类 号：TG146.22[一般工业技术—材料科学与工程]