6082铝合金搅拌摩擦焊接头根部缺陷的微观特征

Microscopic Characteristics of Root Defects in Friction Stir Welded Joints of 6082 Aluminum Alloy

采用光学显微镜和扫描电镜对不同焊接速度(200,300,600mm·min^-1)下6082-T6铝合金搅拌摩擦焊(FSW)接头根部的缺陷进行分析,确定了根部缺陷的微观形貌特征。结果表明:当焊接速度为200mm·min^-1时,接头根部接合面实现了良好的固相连接,其根部缺陷主要为S线缺陷;当焊接速度为300mm·min^-1时,接头根部缺陷主要为以不连续微裂纹形式存在的弱结合缺陷;当焊接速度为600mm·min^-1时,接头根部缺陷主要为呈连续微裂纹形态的未焊透缺陷,在未焊透缺陷向焊核区方向存在呈现不连续微裂纹形式的弱结合缺陷。

Root defects of friction stir welded(FSW)joints of 6082-T6 aluminum alloy at different welding speeds(200,300,600 mm·min^-1)were analyzed by optical microscope and scanning electron microscope,and the microscopic morphology characteristics of the root defects were determined.The results show that when the welding speed was 200 mm·min^-1,the faying surfaces at root of the joint had a good solid phase connection and the root defects were mainly S curve defects.When the welding speed was 300 mm·min^-1,the root defects of the joint were mainly weak bond defects in the form of discontinuous microcracks.When the welding speed was 600 mm·min^-1,the root defects of the joint were mainly incomplete penetration defects in the form of continuous microcracks.The weak bond defects in the form of discontinuous microcrack existed in the location from the incomplete penetration defects to the weld nudget.