Effect of tool tilt angle on strength and microstructural characteristics of friction stir welded lap joints of AA2014-T6 aluminum alloy  

搅拌头倾斜角对搅拌摩擦焊AA2014-T6铝合金焊接接头强度和显微组织的影响（英文）

作　　者：C.RAJENDRAN K.SRINIVASAN V.BALASUBRAMANIAN H.BALAJI P.SELVARAJ 

机构地区：[1]Department of Mechanical Engineering,Sri Krishna College of Engineering and Technology,Coimbatore Tamil Nadu 641008,India [2]Center for Materials Joining and Research(CEMAJOR),Annamalai University,Tamil Nadu 608002,India [3]Aeronautical Development Agency,Bangalore,Karnataka 560017,India

出　　处：《Transactions of Nonferrous Metals Society of China》2019年第9期1824-1835,共12页中国有色金属学报（英文版）

基　　金：Aeronautical Development Agency (ADA), Bangalore, India, for the financial support to carry out this investigation through an R&D project No: FSED 83.07.03

摘　　要：Friction stir welding(FSW)has been extensively adopted to fabricate aluminium alloy joints by incorporating various welding parameters that include welding speed,rotational speed,diameters of shoulder and pin and tool tilt angle.FSW parameters significantly affect the weld strength.Tool tilt angle is one of the significant process parameters among the weld parameters.The present study focused on the effect of tool tilt angle on strength of friction stir lap welding of AA2014-T6 aluminium alloy.The tool tilt angle was varied between 0°and 4°with an equal increment of 1°.Other process parameters were kept constant.Macrostructure and microstructure analysis,microhardness measurement,scanning electron micrograph,transmission electron micrograph and energy dispersive spectroscopy analysis were performed to evaluate the lap shear strength of friction stir lap welded joint.Results proved that,defect-free weld joint was obtained while using a tool tilt angle of 1°to 3°.However,sound joints were welded using a tool tilt angle of 2°,which had the maximum lap shear strength of 14.42 kN and microhardness of HV 132.The joints welded using tool tilt angles of 1°and 3°yielded inferior lap shear strength due to unbalanced material flow in the weld region during FSW.结合各种焊接参数,包括焊接速度、转速、轴肩和搅拌针直径、搅拌头倾斜角等,搅拌摩擦焊(FSW)已经广泛应用于制造铝合金接头。FSW参数能够显著影响焊接强度,其中,搅拌头倾斜角是一种重要的过程参数。因此,本文作者研究搅拌头倾斜角对搅拌摩擦焊铝合金(AA2014-T6)搭接焊接强度的影响。搅拌头倾斜角的变化范围为0°~4°,等值增量为1°,其他参数保持一致。采用宏观和微观组织分析、显微硬度测量、扫描电镜、透射电镜和能谱分析等方法对搅拌摩擦搭接接头的搭接剪切强度进行测定。结果表明,当搅拌头倾斜角为1°~3°时,可获得无缺陷的焊接接头;当倾斜角为2°时,可获得具有最大剪切强度(14.42 kN)和显微硬度(HV 132)的接头。采用1°和3°倾斜角焊接的接头其剪切强度较差,这是搅拌摩擦焊过程中焊接区域内物料流动不平衡导致的。

关 键 词：AA2014 aluminium alloy friction stir lap welding tool tilt angle lap shear strength microstructure 

分 类 号：TG1[金属学及工艺—金属学]