固溶时间对AZG315镁合金显微组织演变的影响及其作用机制  

Effect and mechanism of solution time on microstructure evolution of AZG315 magnesium alloy

作　　者：刘阳力[1] 张金玲[1,2,3] 刘军[1] 于彦冲[1] 王社斌[1,2,3] 许并社[1,2,3] 

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]新材料界面科学与工程教育部重点实验室,山西太原030024 [3]山西省新材料工程技术研究中心,山西太原030024

出　　处：《材料热处理学报》2016年第6期49-54,共6页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51371122);山西省科学基金(2015011068);北京科技大学钢铁冶金新技术国家重点实验室开放项目(KF13-06)

摘　　要：对AZG315镁合金在540℃进行不同时间固溶处理,研究了其显微组织的演变。通过OM、SEM、EDS、XRD对合金显微组织和相组成进行了表征。结果表明,AZG315镁合金中主要含有两种相,一种为α-Mg基体相,另一种为Al2Gd第二相。在固溶处理的过程中,随固溶时间延长,Al2Gd相的形貌发生显著的变化,由铸态下的针状逐次变为棒状、短杆状、颗粒状。然而,这种形貌的演变恰好符合Ostwald熟化理论,并且当固溶时间为16 h时,Al2Gd颗粒相近乎均匀分布在基体中,可以有效的起到第二相强化作用。Microstructure evolution of AZG315 magnesium alloy during solution treatment at 540 ℃ was investigated.The microstructure and phase composition were characterized by OM,SEM,EDS analysis and XRD.The results indicate that two phases mainly exist in AZG315 alloy.One is α-Mg matrix and the other is Al2 Gd phase.In the process of solution treatment,the morphology of the Al2 Gd phase changes enormously.The morphology of the Al2 Gd phase is needle shape,rod-like,short-bar shape and granular in turn during the solution treatment,which conforms with Ostwald ripening theory.The morphology of the Al2 Gd phase becomes granular and it is distributed in the matrix uniformly after solution treatment for 16 h,which results in the efficient strengthening from the second phase.

关 键 词：显微结构 固溶处理 形貌演变 Ostwald熟化理论 

分 类 号：TG146.22[一般工业技术—材料科学与工程]