稀土元素Gd和Sm对AZ81镁合金组织及力学性能的影响.pdfVIP

学兔兔 Feb．2O15 Vo1．64 NO．2 稀土元素Gd和Sm对AZ81镁合金组织及 力学性能的影响 李梅菊，丁雨田 (兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室，甘肃兰州730050) 摘要：利用气体保护下感应熔炼方法制备了AZ8l+(Gd+Sm)合金，采用光学金相(OM)、扫描电镜(SEM)、X射线衍 射分析(XRD1、能谱分析(EDX)和拉伸性能测试等手段，对合金进行了显微组织、力学性能以及断口形貌分析。研究 表明：Gd和Sm的添加使得合金晶粒得到细化，在稀土总含量为2％时细化效果最为明显，基体中形成了稀土一铝化合 物AI：Sm和AlzGd。随着Sm和Gd含量的增加，AZ81合金的室温和高温下的抗拉强度先升高后降低，稀土添加量在2％ ～ 3％时取得最好的强化效果，过量稀土恶化了组织，降低了性能。 关键词：镁合金；组织；力学性能；Gd；Sm 中图分类号：TG146．2 文献标识码：A 文章编号：1001—4977(2015)02～0105—05 E仟ect of Gd and Sm on the MicrOStruCture and Mechanical Properties of AZ81 Magnesium Alloy LI Mei-ju，DING Yu-tian (State Key Laboratory ofAdvanced Processing and Recycling ofNon-Ferrous Metals．Lanzhou University of Technology，Lanzhou 730050，Gansu，China) Abstract： The AZ8 l magnesium alloys with Gd and Sm addition were prepared by medium．fiequency induction melting with gas protection method．The influence of Gd and Sm addition on microstructure and properties Of AZ8 1 alloys was investigated．The microstructure and mechanical properties of the alloys were researched bV 0M，SEM，XRD，EDS and tensile test．The results show that the microstructure is obviously refined with the addition ofGd and Sm． en the I content is 2％．AZ8 1 alloy exhibits best refine effect．With the increase of Sm and Gd the tensile strength of alloys at room temperature and high temperature firstly increases．and then decreases． en the addition amount iS in the range Of 2％一3％，the alloy exhibits best strengthening effect．And the excess addition of rare elements can worse the microstructure and weaken the strengthening effect ofMg 6A1 alloy． Key words：magnesium alloy；microstructure；mechanica1 properties；Gd；Sm 作为目前可应用的最轻的金属结构材