铸态镁合金在累积反向挤压变形中的微观组织演变  

Microstructure evolution of as⁃cast magnesium alloyduring accumulative back extrusion process

作　　者：汪以祥 景灵方[2] 聂志华 陈晨 徐岩 WANG Yixiang;JING Lingfang;NIE Zhihua;CHEN Chen;XU Yan(Fujian Rheomet Light Metal Company Limited,Sanming,Fujian 353300,China;School of Mechanical Engineering,Yanshan University,Qinhuangdao,Hebei 066004,China)

机构地区：[1]福建省瑞奥麦特轻金属有限责任公司,福建三明353300 [2]燕山大学机械工程学院,河北秦皇岛066004

出　　处：《燕山大学学报》2023年第5期411-419,共9页Journal of Yanshan University

基　　金：国家自然科学基金资助项目(51605421);河北省自然科学基金资助项目(E2020203073);河北省教育厅高等学校科技计划青年基金项目(QN2019129)。

摘　　要：本文以铸态AZ91D镁合金为研究对象,在310℃下进行了1、3、6变形循环的累积反向挤压大变形,详细研究了累积反向挤压变形过程中铸态合金第二相形貌和基体组织的演变过程。结果表明Mg17 Al12相先后经历了边缘回溶、局部颈缩、断裂、球化过程,最终演变为弥散分布的细小球状或近球状颗粒。证实了累积反向挤压变形合金的基体组织在剪切变形区得到显著细化,随变形循环次数的增多,晶粒尺寸由初始铸态的113.98μm细化至约2μm。An accumulative back extrusion(ABE)process was carried out for an AZ91D alloy at 310℃for various cycles of 1,3 and 6.Evolution of second phase and grain structure during was investigated.The results reveal that the morphology of Mg17 Al12 phase undergoes the evolution process of edge dissolution,narrowing,necking,fracture,refinement and spheroidization.It is proved that refinement of the ABE process to the matrix grain structure is significant in shear deformation regions.The grain structure is greatly refined from 113.98μm of the as⁃cast structure to 2μm after 6 ABE cycles.

关 键 词：镁合金 累积反向挤压 第二相 组织演变 

分 类 号：TB316[一般工业技术—材料科学与工程]