Effect of tool pin profile on microstructure and tensile properties of friction stir welded dissimilar AA 6061e AA 5086 aluminium alloy joints  

作　　者：M.ILANGOVAN S.RAJENDRA BOOPATHY V.BALASUBRAMANIAN 

机构地区：[1]Department of Mechanical Engineering,College of Engineering Guindy,Anna University [2]Center for Materials Joining & Research (CEMAJOR),Department of Manufacturing Engineering,Annamalai University

出　　处：《Defence Technology（防务技术）》2015年第2期174-184,共11页Defence Technology

基　　金：the support extended by the Centre for Materials Joining & Research (CEMAJOR), Department of Manufacturing Engineering, Annamalai University, Annamalai Nagar, India to carry out this research

摘　　要：Joints between two different grades of aluminium alloys are need of the hour in many light weight military structures.In this investigation,an attempt has been made to join the heat treatable(AA 6061) and non-heat treatable(AA 5086) aluminium alloys by friction stir welding(FSW)process using three different tool pin profiles like straight cylindrical,taper cylindrical and threaded cylindrical.The microstructures of various regions were observed and analyzed by means of optical and scanning electron microscope.The tensile properties and microhardness were evaluated for the welded joint.From this investigation it is founded that the use of threaded pin profile of tool contributes to better flow of materials between two alloys and the generation of defect free stir zone.It also resulted in higher hardness values of 83 HV in the stir zone and higher tensile strength of 169 MPa compared to other two profiles.The increase in hardness is attributed to the formation of fine grains and intermetallics in the stir zone,and in addition,the reduced size of weaker regions,such as TMAZ and HAZ regions,results in higher tensile properties.Joints between two different grades of aluminium alloys are need of the hour in many light weight military structures. In this investigation, an attempt has been made to join the heat treatable （AA 6061） and non-heat treatable （AA 5086） aluminium alloys by friction stir welding （FSW） process using three different tool pin profiles like straight cylindrical, taper cylindrical and threaded cylindrical. The microstructures of various regions were observed and analyzed by means of optical and scanning electron microscope. The tensile properties and microhardness were evaluated for the welded joint. From this investigation it is founded that the use of threaded pin profile of tool contributes to better flow of materials between two alloys and the generation of defect free stir zone. It also resulted in higher hardness values of 83 HV in the stir zone and higher tensile strength of 169 MPa compared to other two profiles. The increase in hardness is attributed to the formation of fine grains and intermetallics in the stir zone, and in addition, the reduced size of weaker regions, such as TMAZ and HAZ regions, results in higher tensile properties.

关 键 词：摩擦搅拌焊 铝合金接头 焊接接头 组织与性能 轮廓 扫描电子显微镜 异种 刀具 

分 类 号：TG457.14[金属学及工艺—焊接]