添加微量锆、铒对铸造Al-8.25Zn-2.4Mg-2.3Cu合金组织与力学性能的影响  

Effect of Trace Zr and Er on Microstructure and Mechanical Properties of As-Cast Al-8.25Zn-2.4Mg -2.3Cu Based Alloy

作　　者：梁维盛[1] 杨福宝[1] 徐骏[1] 张志峰[1] 石力开[1] 

机构地区：[1]北京有色金属研究总院复合材料研究中心,北京100088

出　　处：《稀有金属》2009年第5期631-637,共7页Chinese Journal of Rare Metals

基　　金：国家973计划资助项目(2006CB605203)

摘　　要：采用光学显微镜、扫描电镜和X射线衍射等方法研究了微量Er和Zr元素对Al-8.25Zn-2.4Mg-2.3Cu合金铸锭组织的细化作用及其细化机制,同时考察了微合金化元素对试验合金力学性能的影响。结果表明:单独添加Zr对Al-8.25Zn-2.4Mg-2.3Cu合金铸锭组织有一定的细化作用,而复合添加Zr和Er则对Al-8.25Zn-2.4Mg-2.3Cu合金铸锭组织产生强烈的细化效果,分析表明其细化效应与合金凝固过程中Al8Cu4Er相、Al3Er相和Al3Zr等复合质点的析出及微量元素在凝固界面前沿的富集有关。经过T6处理,Al-8.25Zn-2.4Mg-2.3Cu-0.18Zr-0.40Er合金的抗拉强度σb为600MPa;延伸率达到8%。与7075合金相比,试验合金的强度与塑性均获得大幅度提高。The grain refinement effect and mechanism by addition of trace Zr and Er in as-cast Al-8.25Zn- 2.4Mg-2.3Cu based alloy were studied by means of OM, SEM, EDS and X-ray diffraction. The influence of the trace elements on mechanical properties was studied. Alone addition of Zr to Al-8.25Zn-2.4Mg-23Cu refined grains to a certain degree. Joint addition of Er and Zr had strong grain refinement effect on as-cast microstrocture. AlsCu4Er/M3Er and AI3Er composite particles were effective for grain refinement during heterogeneous nucleation in M-Zn-Mg-Cu alloy. After strengthening solution and T6 treatment, the tensile strength and elongation of M-8.25Zn-2.4Mg-23Cu-0.18Zr-0.40Er alloys were 600 MPa and 8% respectively. As to 7075 alloys, the strength and plasticity of the studied alloy were dramatically increased.

关 键 词：Al-Zn—Mg—Cu合金 Er与Zr复合添加 晶粒细化 力学性能 

分 类 号：TG425[金属学及工艺—焊接]