等径角挤压轨道交通车辆用7005铝合金的组织和力学性能  

Microstructure and Mechanical Properties of Equal Channel Angular Pressing 7005 Aluminum Alloy for Rail Transit Vehicles

作　　者：黎志勇 陈家欣 杨斌 覃羡烘 罗泽鹏 LI Zhiyong;CHEN Jiaxin;YANG Bin;QIN Xianhong;LUO Zepeng(Institute of Intelligent Manufacturing,Guangdong Institute of Technology,Zhaoqing 526100,China;Faculty of Science and Technology,National University of Malaysia,Selangor 43600,Malaysia;National Quality Supervision and Inspection Center for Knives,Scissors and Daily Metal Tools,Yangjiang 529539,China)

机构地区：[1]广东理工学院智能制造学院,广东肇庆526100 [2]马来西亚国民大学工程与技术学院,马来西亚雪兰莪43600 [3]国家刀剪及日用金属工具质量监督检验中心,广东阳江529539

出　　处：《热加工工艺》2023年第21期133-136,共4页Hot Working Technology

基　　金：广东理工学院科技项目(2022GKJTD002);广东省普通高校特色创新项目(2021KTSCX156)。

摘　　要：在室温下对350℃×2 h退火后的轨道交通车辆用7005铝合金进行了2道次等径角挤压,利用光学显微镜、扫描电镜和电子拉伸试验机对合金挤压前后的显微组织、力学性能及断口形貌进行分析。结果表明:随着挤压道次的增加,试样显微组织细化,力学性能提升,2道次后,晶粒大小约为3μm,甚至出现1μm以下的小晶粒;抗拉强度、屈服强度和断后伸长率分别为384.33 MPa、332.60 MPa、14.2%,分别比等径角挤压前提高53.08 MPa、79.48 MPa、2.8%,晶粒细化明显,力学性能得到大幅改善。7005 aluminum alloy for rail transit vehicles annealed at 350℃×2 h was subjected to 2 passes equal channel angular extrusion at room temperature.The optical microscope,scanning electron microscope and electronic tensile testing machine were used to analyze the microstructure,mechanical properties and fracture morphology of the alloy before and after extrusion.The results show that with the increase of extrusion pass,the sample microstructure is refined and the mechanical properties are improved.After 2 times,the grain size is about 3μm,or even small grains below 1μm;the tensile strength,yield strength and elongation after fracture are 384.33 MPa,332.60 MPa and 14.2%,respectively,which increases 53.08 MPa,79.48 MPa and 2.8%compared with those of the equal diameter angle before extrusion,respectively.The grain refinement is obvious and the mechanical properties are greatly improved.

关 键 词：等径角挤压(ECAP) 显微组织 断口形貌 7005铝合金 

分 类 号：TG379[金属学及工艺—金属压力加工]