热处理对铸造Mg-4Y-3Nd-1.5Al合金显微组织和力学性能的影响  

Effect of Heat Treatment on Microstructure and Mechanical Properties of Mg-4Y-3Nd-1.5Al Alloy

作　　者：冯义成[1] 王雷[1] 付原科[1] 赵思聪[1] 王丽萍[1] 郭二军[1] Feng Yicheng;Wang Lei;Fu Yuanke;Zhao Sicong;Wang Liping;Guo Erjun(School of Materials Science and Engineering,Harbin University of Science and Technology,Harbin 150040,China)

机构地区：[1]哈尔滨理工大学材料科学与工程学院,黑龙江哈尔滨150040

出　　处：《稀有金属材料与工程》2021年第5期1826-1832,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51804090);黑龙江省科学基金(E2018045)。

摘　　要：通过显微组织分析和力学性能测试等试验手段,研究了热处理对Mg-4Y-3Nd-1.5Al合金显微组织和力学性能的影响。结果表明:铸态合金组织中第二相主要为Mg5RE、Mg24RE5和Al2RE相,经固溶处理后(525℃/6 h+550℃/12 h),Mg5RE、Mg24RE5相完全溶解,Al2RE不发生溶解。Mg-4Y-3Nd-1.5Al合金具有明显的时效硬化行为,经固溶+时效处理后,合金的力学性能显著提高。经固溶(525℃/6 h+550℃/12 h)+峰时效(225℃/10 h)处理后,Mg-4Y-3Nd-1.5Al合金屈服强度、抗拉强度和延伸率分别为182 MPa、267 MPa和6.5%。获得良好的力学性能与合金中析出高密度的细小β’’和β’相有关。The microstructure and mechanical properties of Mg-4 Y-3 Nd-1.5 Al alloy with different heat treatment conditions were carried out by microstructural analysis and mechanical property testing.The results show that there are Mg5 RE,Mg24RE5 and Al2 RE intermetallic phases in as-cast Mg-4 Y-3 Nd-1.5 Al alloy and the Mg5 RE and Mg24RE5 phases dissolve intoα-Mg matrix and Al2 RE phases is stable in solid-solution treated Mg-4 Y-3 Nd-1.5 Al alloy.The Mg-4 Y-3 Nd-1.5 Al alloy has an obvious aging hardening effect and the mechanical property can be improved obviously by solution+aging treatment.The yield strength,ultimate tensile strength and elongation of Mg-4 Y-3 Nd-1.5 Al alloy after solution(525℃/6 h+550℃/12 h)+peak aging(225℃/10 h)are 182 MPa,267 MPa and 6.5%,respectively.The high density and fine precipitationβ"andβ’are responsible for the excellent mechanical properties of heat treated Mg-4 Y-3 Nd-1.5 Al alloy.

关 键 词：镁合金 热处理 显微组织 力学性能 

分 类 号：TG146.22[一般工业技术—材料科学与工程]