Mg-8Zn-4Al-(0~1)Sr镁合金铸态组织中的第二相研究  

The second phases in as-cast Mg-8Zn-4Al-(01)Sr magnesium alloys

作　　者：吴菊英 李景仁 张晋涛[1] 罗丽 杨明波[3] 吴璐[4] 潘虎成 WU Juying;LI Jingren;ZHANG Jintao;LUO Li;YANG Mingbo;WU Lu;PAN Hucheng(Department of Materials Engineering,Sichuan Engineering Technical College,Deyang,Sichuan 618000,P.R.China;School of Materials Science and Engineering,Northeastern University,Shenyang 110819,P.R.China;Chongqing University of Technology,School of Materials Science and Engineering,Chongqing 400054,P.R.China;State Key Laboratory of Nuclear Fuel and Materials,Nuclear Power Institute of China,Chengdu 610041,P.R.China)

机构地区：[1]四川工程职业技术学院材料工程系,四川德阳618000 [2]东北大学材料科学与工程学院,沈阳110819 [3]重庆理工大学材料科学与工程学院,重庆400054 [4]中国核动力研究设计院核燃料及材料国家重点实验室,成都610041

出　　处：《重庆大学学报》2021年第4期117-128,共12页Journal of Chongqing University

基　　金：国家自然科学基金资助项目(U1610253,51971053);中央高校基本科研业务费项目(N2002011);辽宁省沈阳材料科学国家研究中心联合研发基金(2019JH3/30100040)。

摘　　要：通过扫描电镜观察(SEM)、能谱分析(EDS)、X射线衍射分析(XRD)以及差热分析(DSC)等实验手段,系统地研究了添加微量Sr元素(质量分数0~1%)对铸态Mg-8Zn-4Al(ZA84)镁合金组织中的第二相种类的影响,并阐明了第二相形成与演变的内在机理。实验结果表明:未添加Sr元素的铸态Mg-8Zn-4Al合金组织由Q准晶相和少量Mg_(32)(Al, Zn)_(49)相组成。添加Sr元素后,合金铸态组织中均存在Al_4Sr和Mg_(32)(Al, Zn)_(49)相;其中Al_4Sr相随Sr含量增加而增加,Mg_(32)(Al, Zn)_(49)相随Sr含量增加而减少。在Mg_(32)(Al, Zn)_(49)相中Sr元素以未固溶和固溶两种形式存在,其中未固溶Sr元素的Mg_(32)(Al, Zn)_(49)相具有相对较高的Zn原子浓度和较低的Al原子浓度。相关结果将为第二相析出强化型Mg-8Zn-4Al合金的高强化与耐热化设计提供必要的理论支撑。To systematically investigate the effect of Sr addition on the second phases in the as-cast Mg-8Zn-4Al magnesium alloy and provide the theoretical basis for the design of the Mg-Zn-Al series alloys containing Sr element,the type and formation mechanism of second phases in the ZA84 as-cast magnesium alloys with low Sr mass fractions(0.1%,0.3%,and 1.0%)were investigated and analyzed by using scanning electron microscope(SEM),energy dispersive spectrometer(EDS),differential scanning calorimetry(DSC),and X-ray diffractometer(XRD).The results indicate that for the ZA84 as-cast alloy without Sr addition,besides the quasicrystal phase(Q),an extra Mg 32(Al,Zn)49 phase with a small amount is found to exist in the alloy.With Sr addition,there are Al4Sr and Mg 32(Al,Zn)49 phases in the as-cast alloy;the Al4Sr phase increases and Mg 32(Al,Zn)49 phase decreases with increase of Sr content.In the Mg 32(Al,Zn)49 phases of the as-cast Mg-8Zn-4Al-(0.1-1)Sr magnesium alloys,Sr mainly exists in two forms,i.e.indissolved and dissolved Sr atoms;in the Mg 32(Al,Zn)49 phase where Sr atoms are not dissolved,the Zn concentration is relatively high and Al concentration is low.The results provide the necessary theoretical support for the design of reinforced and heat-resistant Mg-8Zn-4Al alloy.

关 键 词：镁合金 Sr合金化 第二相 衍射分析 能谱 

分 类 号：TG136[一般工业技术—材料科学与工程]