Microstructure evolution along thickness in double-side friction stir welded 7085 Al alloy  

7085铝合金双面搅拌摩擦焊缝沿板厚方向组织演变规律（英文）

作　　者：徐韦锋[1] 刘金合[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室陕西省摩擦焊接技术实验室,西安710072

出　　处：《Transactions of Nonferrous Metals Society of China》2015年第10期3212-3222,共11页中国有色金属学报（英文版）

基　　金：Project(51405392)supported by the National Natural Science Foundation of China;Project(20136102120022)supported by the Research Fund for the Doctoral Program of Higher Education of China;Project(2013JQ6001)supported by the Natural Science Foundation of Shaanxi Province,China;Project(3102015ZY023)supported by the Fundamental Research Funds for the Central Universities,China

摘　　要：The microstructure evolution in the weld zone of double-side friction stir welded（DS-FSWed） 7085-T7452 Al alloy was investigated by the electron backscatter diffraction method.The results indicate that DS-FSW process results in substantial grain refinement.The misorientation angle distribution shows a very high volume fraction of high angle grain boundary（HAGB）（above 75%） under DS-FSW condition at rotational rate of 300 r/min.The fraction of HAGB rapidly decreases with increasing the rotational rate from 300 to 950 r/min,and the obvious growth of grain in the weld nugget zone（WNZ） is presented.The average grain sizes in the elongated grains of thermal-mechanical affected zone（TMAZ） and partially equiaxed and coarser grains of thermal affected zone（HAZ） are 7.3 and 15.7 μm with the fractions of HAGBs less than 43% and 30%,respectively.The intensities of（100）,（110） and（111） pole figures in the WNZ obviously decrease when compared with those in the BM and present significantly difference along the thickness direction of plate.利用电子背散射衍射技术(EBSD),研究7085-T7452铝合金双面搅拌摩擦焊缝组织演变规律。结果表明:相对于7085-T7452铝合金母材,双面搅拌摩擦焊缝的晶粒发生明显细化,焊缝的大角度晶界体积分数在300 r/min的旋转速度时较高(75%以上),随着旋转速度升高到950 r/min而降低。热-机影响区被拉长晶粒和热影响区部分等轴粗大晶粒的平均尺寸分别是7.3和15.7μm,且大角度晶界体积分数分别为43%和30%。与母材相比,双面搅拌摩擦焊缝焊核区(100)、(110)和(111)极图的强度降低,且沿板厚方向存在较大的差异。

关 键 词：double-side friction stir weld 7085 Al alloy microstructure 

分 类 号：TG453.9[金属学及工艺—焊接] TG457.14