Effect of number of adjusting times on fatigue properties of FSW joint of 6082-T6 aluminum alloy

调修次数对6082-T6铝合金搅拌摩擦焊接头疲劳性能的影响 Effect of number of adjusting times on fatigue properties of FSW joint of 6082-T6 aluminum alloy 刘国田 LIU Guotian 1 2 first-author 段泽斌 DUAN Zebin 1 2 刘凯 LIU Kai 1 陈海宽 CHEN Haikuan 1 李永印 LI Yongyin 1 中车唐山机车车辆有限公司 中车唐山机车车辆有限公司 Hebei Railway Vehicle Bogie Technology Innovation Center Hebei Railway Vehicle Bogie Technology Innovation Center 河北省轨道车辆转向架技术创新中心  河北省轨道车辆转向架技术创新中心  CRRC Tangshan Co.,Ltd. CRRC Tangshan Co.,Ltd. 平头搅拌针调修是指在原有焊缝背面用无搅拌针的搅拌头对焊缝再次进行搅拌摩擦焊,使焊缝温度升高,改善FSW接头性能。对平头搅拌针不同调修次数的高速列车用6082-T6铝合金搅拌摩擦焊接头进行脉动拉伸疲劳试验,利用扫描电镜观察分析疲劳断口,试验结果表明:铝合金搅拌摩擦焊接头指定寿命为1×107次的中值疲劳极限随着搅拌针调修次数的增加而升高。平头搅拌针调修两次时焊接接头的疲劳极限强度较高,焊缝背面边缘是本次试验集中产生裂纹的部位。启裂区和扩展区疲劳纹清晰;终断区为深韧窝状花样的韧性断口。 Through pulsating tensile fatigue test, the friction stir welding（FSW） joints of 6082-T6 aluminum alloy used for high speed train were studied with different number of adjusting times by the flat stir pin, and the fatigue fractures were observed and analyzed by SEM. The results show that the specified life of FSW joints of aluminum alloy is median value fatigue limit strength of 1 ×107, which rises as the number of adjusting times increases. The welded joints have higher fatigue limit strength with twice adjusting by flat stir pin, and the cracks are mainly concentrated at the back edge of the welds. The fatigue cracks in the crack initiation zone and extension zone are vivid, and the final broken zone is the ductile fracture with deep dimple pattern. 调修次数 搅拌摩擦焊 疲劳极限 摩擦热 平头搅拌针 number of adjusting times friction stir welding fatigue properties friction heat flat stir pin TG453.9 2022-03-08 11 51