镁含量对超高强铝合金屈服强度淬火敏感性的影响  

Effect of Mg content on quenching sensitivity relative to yield strength of ultra-high strength aluminum alloy

作　　者：刘安民 刘胜胆[1,2] 杨梦楚 张梦晗 周爱华 周智强 LIU Anmin;LIU Shengdan;YANG Mengchu;ZHANG Menghan;ZHOU Aihua;ZHOU Zhiqiang(School of Materials Science and Engineering,Central South University,Changsha 410083,China;Key Laboratory of Non-Ferrous Metal Materials Science and Engineering,Ministry of Education,Central South University,Changsha 410083,China;Yunnan Aijia Aluminum Co.,Ltd.,Qujing 655335,China)

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]中南大学有色金属材料科学与工程教育部重点实验室,长沙410083 [3]云南爱家铝业有限公司,曲靖655335

出　　处：《中国有色金属学报》2024年第5期1519-1528,共10页The Chinese Journal of Nonferrous Metals

基　　金：云南省科技人才与平台计划资助项目(202205AF150045)。

摘　　要：通过浸入式末端淬火、室温拉伸测试、电导率测试、相图和连续冷却转变曲线计算、扫描电镜、电子背散射衍射和透射电镜等方法,研究了Mg含量(1%、2%、3%,质量分数)对Al-9Zn-xMg-1Cu合金屈服强度淬火敏感性的影响。结果表明:Mg含量越高,合金屈服强度随着淬火速率减小而下降的比率越高,即淬火敏感性越高。合金中的淬火诱导相均为η相和T相,Mg含量升高提高了这些相析出的临界淬火速率,同时增加了它们的数量和尺寸。结合电导率和淬火诱导相面积分数结果,从淬火诱导相的析出驱动力和非均匀形核位点数量差异的角度,探讨了Mg含量影响合金淬火敏感性的机理。The effect of Mg content(1%,2%and 3%,mass fraction)on the quenching sensitivity relative to yield strength of Al-Zn-Mg-Cu alloy was studied by immersion end-quenching technique,room temperature tensile test,electrical conductivity test,calculation of phase diagram and continuous cooling transformation diagram,scanning electron microscopy,electron backscatter diffraction and transmission electron microscopy.The results show that higher content of Mg leads to higher reduction rate of yield strength due to the decrease of quenching rate,and therefore quenching sensitivity is higher.The quenching-induced phases in the alloys areηand T phase.The increase of Mg content increases the critical quenching rates for precipitation,the quantities and sizes of these phases.Combined with the results of electrical conductivity and quenching-induced phase area fraction,the mechanism of Mg content affecting quenching sensitivity was discussed in terms of the difference of driving force and nucleation sites for precipitation of quenching-induced phase.

关 键 词：AL-ZN-MG-CU合金 Mg含量 屈服强度 淬火敏感性 

分 类 号：TG146.2[一般工业技术—材料科学与工程]