2519A-T87铝合金厚板组织和性能不均匀性研究  

Research on inhomogeneity of microstructure and properties of 2519A-T87 aluminum alloy thick plate

作　　者：刘文辉 曹平 赵晨冰 黄浩 朱必武[3] LIU Wen-hui;CAO Ping;ZHAO Chen-bing;HUANG Hao;ZHU Bi-wu(School of Materials Science and Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;Jianglu Machinery Electronics Group Co.,Ltd.,Xiangtan 411201,China;School of Mechanical and Electrical Engineering,Hunan University of Science and Technology,Xiangtan 411201,China)

机构地区：[1]湖南科技大学材料科学与工程学院,湖南湘潭411201 [2]江麓机电集团有限公司,湖南湘潭411201 [3]湖南科技大学机电工程学院,湖南湘潭411201

出　　处：《塑性工程学报》2021年第1期106-113,共8页Journal of Plasticity Engineering

基　　金：国家自然科学基金面上项目(51875197);国防科技重点实验室基金资助项目(6142912180103);湖南省自然科学基金资助项目(2020JJ6027)。

摘　　要：采用金相显微镜、扫描电镜、透射电镜、室温拉伸测试、硬度测试等手段,研究了51 mm厚的2519A-T87铝合金板材不同厚度层的微观组织与力学性能。结果表明:沿板材厚度方向,合金的组织和强度呈不均匀分布。从表层到中间层,晶粒的纵横比增加;合金中第二相沿轧向呈链状分布,表层第二相尺寸均匀、细小,从表层到中间层,第二相尺寸逐渐增大,面积分数逐渐增加;从板材表层到中间层,时效析出相面积分数减小,无沉淀析出带变宽,抗拉强度逐渐降低,伸长率有所增加;表层断裂模式以韧窝断裂为主,从表层到中间层,由粗大第二相引发的孔洞尺寸增大,沿晶裂纹增多,沿晶断裂比例增加。The microstructure and mechanical properties of different layers of 2519 A-T87 aluminum alloy plate with a thickness of 51 mm were investigated by means of optical microscopy,scanning electron microscopy(SEM),transmission electron microscopy(TEM),room temperature tensile test and hardness test.The results show that the microstructure and strength distribution of alloy along thickness direction of the plate is inhomogeneous.The aspect ratio of the grains increases from the surface layer to the intermediate layer.The second phase in alloy is distributed in a chain-like shape along rolling direction,and the second phase in the surface layer is uniform and fine.The size of the second phase and the area fraction gradually increase from the surface layer to the intermediate layer.The area fraction of the precipitates decreases from the surface layer to the intermediate layer.The participate free zone becomes wider,the tensile strength gradually decreases,and the elongation increases from the surface layer to the intermediate layer.Dimple fracture is the main fracture mode of the surface layer.The size of hole caused by the bulky second phase,the intergranular crack and the proportion of intergranular fracture increases from the surface layer to the intermediate layer.

关 键 词：2519A铝合金 不均匀性 第二相 拉伸性能 

分 类 号：TG146.1[金属学及工艺—金属材料]