Microstructure and tribological behavior of Mg-Gd-Zn-Zr alloy with LPSO structure  

具有长周期结构的Mg–Gd–Zn–Zr合金的微结构和摩擦学行为(英文)

作　　者：曹丽杰[1] 吴玉娟[2] 彭立明[2] 王渠东[2] 丁文江[2] 

机构地区：[1]上海工程技术大学机械工程学院,上海201600 [2]上海交通大学轻合金精密成型国家工程研究中心,上海200240

出　　处：《Transactions of Nonferrous Metals Society of China》2014年第12期3785-3791,共7页中国有色金属学报（英文版）

基　　金：Projects(51304135,50971089)supported by the National Natural Science Foundation of China;Project(A1420110045)supported by National Defense Basic Research Plan,China;Project(11QH1401200)supported by the Shanghai Phospherus Program,China;Project(NCET-11-0329)supported by the New Century Excellent Talents in University of Ministry of Education of China

摘　　要：A Mg-14.28Gd-2.44Zn-0.54Zr （mass fraction, %） alloy was prepared by conventional ingot metallurgy （I/M）. The microstructure differences in as-cast and solution-treated alloys were investigated. Sliding tribological behaviors of the as-cast and solution-treated alloys were investigated under oil lubricant condition by pin-on-disc configuration. The wear loss and friction coefficients were measured at a load of 40 N and sliding speeds of 30-300 mm/s with a sliding distance of 5000 m at room temperature. The results show that the as-cast alloy is mainly composed ofα-Mg solid solution, the lamellar 14H-type long period stacking ordered （LPSO） structure within matrix, andβ-[（Mg,Zn）3Gd] phase. However, most of theβ-phase transforms to X-phase with 14H-type LPSO structure after solution heat treatment at 773 K for 35 h （T4）. The solution-treated alloy presents low wear-resistance, because the hard β-phase is converted into thermally-stable, ductile and soft X-Mg12GdZn phase with LPSO structure in the alloy.利用传统的熔铸法制备Mg-14.28Gd-2.44Zn-0.54Zr合金,研究铸态和固溶态合金的微结构。利用销-盘装置研究铸态和固溶态合金的室温润滑滑动摩擦磨损行为研究。在外载荷为40 N,滑动速度为30-300 mm/s以及滑行路程为5000 m情况下,测量磨损率和摩擦因数。研究结果表明：铸态合金主要由α-Mg固溶体、分布在基体内的层片状的14H型长周期结构（LPSO）和β-[（Mg,Zn）3Gd]相组成。经过温度为773 K固溶处理35 h后,大量的β相转变成具有14H型X相LPSO结构。由于固溶处理后大量β相转变为热稳定的韧性X-Mg12Gd Zn长周期结构相,固溶合金呈现较低的抗磨损能力。

关 键 词：Mg-Gd-Zn-Zr alloy long period stacking ordered （LPSO） structure MICROSTRUCTURE friction wear 

分 类 号：TG146.22[一般工业技术—材料科学与工程]