Mg-Gd-Y-Zn-Zr镁合金的LPSO相演化及其强化机制  

LPSO phase evolution and strengthening mechanism of Mg-Gd-Y-Zn-Zr magnesium alloy

作　　者：张林林 郭俊卿[1,2] 董帅 皇涛 陈拂晓[1,2] ZHANG Lin-lin;GUO Jun-qing;DONG shuai;HUANG tao;CHEN Fu-xiao(School of Materials Science and Technology,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,Luoyang 471023,China;Luoyang Institute of Special Materials Research,Luoyang 471023,China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳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,河南洛阳471023 [3]洛阳特种材料研究院,河南洛阳471023

出　　处：《塑性工程学报》2024年第12期185-194,共10页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51905156);河南省高等学校重点项目(20A460014);河南省自然科学基金优秀青年基金资助项目(202300410122);浙江省科技计划项目(2022C01081)。

摘　　要：为了研究LPSO相对镁合金力学性能的影响,选取挤压态Mg-8.24Gd-2.79Y-1.97Zn-0.52Zr镁合金为研究对象,通过热处理工艺获得了不同形貌和体积分数的LPSO相,采用光学显微镜、扫描电镜、能谱仪和电子拉伸试验机等研究了Mg-Gd-Y-Zn-Zr镁合金的微观组织演化特点及强化机制。结果表明,在520℃时,随着固溶时间的增加,LPSO相逐渐溶解,在固溶45 h时炉冷后LPSO相转化为层片状14H-LPSO相;固溶处理后材料强度降低,主要缘于晶粒长大、块状18R-LPSO相的减少以及层片状14H-LPSO相的比例增加;经固溶时效后强度升至369.4 MPa,增幅达11%,强化机制为时效析出强化,其对强度的贡献为45%左右,即通过热处理工艺可以实现LPSO相微观组织及力学性能的有效调控。To study the effect of LPSO phase on the mechanical properties of magnesium alloy,the as-extruded Mg-8.24Gd-2.79Y-1.97Zn-0.52Zr magnesium alloy was selected as the research object,the LPSO phases with different morphologies and volume fractions were obtained by heat treatment process.The microstructure evolution characteristics and strengthening mechanism of Mg-Gd-Y-Zn-Zr magnesium alloy were studied by means of optical microscope,scanning electron microscope,energy dispersive spectrometer and electron-ic tensile testing machine.The results show that the LPSO phase gradually dissolves with the increase of solid solution time at 520℃.Af-ter solid solution for 45 h,the LPSO phase transforms into lamellar 14H-LPSO phase after furnace cooling.The strength of the material decreases after solution treatment,which is mainly due to the grain growth,the decrease of the block 18R-LPSO phase and the increase of the proportion of the lamellar 14H-LPSO phase.After solution and aging treatment,the strength of LPSO phase increases to 369.4 MPa,with increase amplitude of 11%.The strengthening mechanism is aging precipitation strengthening,which contributes about 45%to the strength.Therefore,the microstructure and mechanical properties of LPSO phase can be effectively controlled by heat treatment process.

关 键 词：Mg-Gd-Y-Zn-Zr合金 LPSO相 微观组织 力学性能 强化机制 

分 类 号：TP391.7[自动化与计算机技术—计算机应用技术] TQ325.9[自动化与计算机技术—计算机科学与技术]