微量Sc、Er复合添加对Al-7Mg-Zr合金微观组织与力学性能的影响  

Effects of Trace Sc/Er Co-Addition on Microstructure and Mechanical Properties of Al-7Mg-Zr Alloy

作　　者：刘帅 黄宏锋 韦莉莉 戴海桃 姜迈 贾子兴 LIU Shuai;HUANG Hongfeng;WEI Lili;DAI Haitao;JIANG Mai;JIA Zixing(Key Laboratory of New Processing Technology for Nonferrous Metal&Materials,Ministry of Education,Guilin University of Technology,Guilin 541004,China;College of Materials Science and Engineering,Guilin University of Technology,Guilin 541004,China)

机构地区：[1]桂林理工大学广西有色金属及特色材料加工教育部重点实验室,广西桂林541004 [2]桂林理工大学材料科学与工程学院,广西桂林541004

出　　处：《热加工工艺》2022年第6期51-55,61,共6页Hot Working Technology

基　　金：广西中青年教师基础能力提升计划资助项目(2019KY0265);桂林理工大学博士科研启动基金资助项目(GLUTQD2016012)。

摘　　要：以Al-7Mg-Zr合金为基体,用半连续铸造添加稀土元素Er和Sc制备Al-7Mg-0.2Zr-0.3Er、Al-7Mg-0.2Zr-0.3Sc和Al-7Mg-0.2Zr-0.15Sc-0.3Er合金。研究了微量Sc、Er添加对Al-7Mg-Zr合金微观组织与力学性能的影响。结果表明,单独添加Sc或Sc、Er复合添加都能降低合金铸锭的平均晶粒尺寸,相比之下,只添加Er对铸锭组织细化效果不明显。合金经350℃/12 h均匀化处理后,在Al-7Mg-0.2Zr-0.3Sc和Al-7Mg-0.2Zr-0.15Sc-0.3Er合金中析出均匀分布的纳米级Al3(Sc,Zr)、Al3(Er,Zr)粒子,产生明显的强化效果,使合金抗拉强度分别提高至324、301 MPa;然而在Al-7Mg-0.2Zr-0.3Er合金中析出的Al3(Sc,Zr)粒子尺寸较大,强化效果相对较弱,合金抗拉强度仅为236 MPa。Taking Al-7Mg-Zr alloy as matrix,Al-7Mg-0.2Zr-0.3Er,Al-7Mg-0.2Zr-0.3Sc and Al-7Mg-0.2Zr-0.15 alloys were fabricated by semi-continuous chill casting ingot with the co-addition of trace Sc and Er.The effects of trace Sc,Zr addition on the microstructure and mechanical properties of these alloys were investigated.The results show that the addition of Sc or co-addition Sc/Er are both able to decrease the average grain size of ingots,by contrast,the grain refinement effect of addition Er is not obvious.After 350℃/12 h homogenization treatment,many uniformly distributed nano-scale Al3(Sc,Zr)/Al3(Er,Zr)precipitate in Al-7Mg-0.2Zr-0.3Sc and Al-7Mg-0.2Zr-0.15Sc-0.3Er alloy matrix,which can create remarkable strengthening and the ultimate tensile strength of the above alloys increases to 324 MPa and 301 MPa,respectively.However,the Al3(Er,Zr)precipitating in Al-7Mg-0.2Zr-0.3Er alloy have large size and relatively weak strengthening effect,therefore,the tensile strength of the alloy is only 236 MPa.

关 键 词：Al-7Mg-Zr合金 稀土元素 均匀化处理 晶粒尺寸 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]