热处理对Mg-11Gd-3Y-0.6Ca-0.5Zr合金显微组织和腐蚀行为的影响  

Effect of Heat Treatment Process on Microstructure and Corrosion Behavior of Mg-11Gd-3Y-0.6Ca-0.5Zr Alloy

作　　者：张帅 李全安[1,2] 朱宏喜 陈晓亚[1,3] 王颂博 关海昆[1] ZHANG Shuai;LI Quan’an;ZHU Hongxi;CHEN Xiaoya;WANG Songbo;GUAN Haikun(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,China;Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology,Henan Province,Luoyang 471023,China;School of Materials Science and Engineering,Xi’an University of Technology,Xi’an 740048,China)

机构地区：[1]河南科技大学材料科学与工程学院,洛阳471023 [2]有色金属新材料与先进加工技术省部共建协同创新中心,洛阳471023 [3]西安理工大学材料科学与工程学院,西安740048

出　　处：《材料导报》2020年第20期20070-20075,共6页Materials Reports

基　　金：国家自然科学基金(51571084,51171059)。

摘　　要：本工作以Mg-11Gd-3Y-0.6Ca-0.5Zr合金为研究对象,对其进行固溶和时效热处理。采用金相显微镜、带能谱的扫描电镜、X射线衍射仪对热处理前后及腐蚀后合金的显微组织和物相进行分析,并采用静态失重法、电化学测试方法研究了热处理前后合金的耐腐蚀性。结果表明:合金铸态组织由α-Mg基体和沿晶分布的粗大共晶相Mg 5Gd、Mg 24 Y 5和Mg 2Ca组成,经固溶时效后,共晶相种类没有改变,但第二相变得细小、弥散,呈颗粒状和短棒状均匀分布在基体上。在3.5%(质量分数)NaCl溶液中,热处理显著提高了合金的耐蚀性,其中,时效态合金的腐蚀速率最小,自腐蚀电位最高,腐蚀电流密度最小,合金的耐蚀性最好,表现为轻微的均匀腐蚀,其次为固溶态、铸态。合金表面的腐蚀产物主要为Mg(OH)2。In this paper,Mg-11Gd-3Y-0.6Ca-0.5Zr alloy was taken as the research object,and solid solution and aging heat treatment are performed.Metallographic microscope,scanning electron microscope with energy spectrum,X-ray diffractometer were used to analyze the microstructure and phase of the alloy before and after heat treatment and corrosion,and the static weight loss method and electrochemical test method were used to study the corrosion resistance of the alloy before and after heat treatment.The results show that the as-cast microstructure of the alloy is composed ofα-Mg matrix and the coarse eutectic phases Mg 5Gd,Mg 24 Y 5 and Mg 2Ca,which are distributed along the grain.In 3.5wt%NaCl solution,heat treatment significantly improves the corrosion resistance of the alloy.Among them,the corrosion rate of the aging alloy is the lo-west,the self-corrosion potential is the highest,the corrosion current density is the lowest,and the corrosion resistance of the alloy is the best,followed by the solid solution state and the casting state.The corrosion products on the surface of the alloy are mainly Mg(OH)2.

关 键 词：Mg-11Gd-3Y-0.6Ca-0.5Zr 固溶 时效 显微组织 腐蚀 

分 类 号：TG146.2[一般工业技术—材料科学与工程]