摘要
在相同工艺参数下,对6005-T6铝合金型材双轴肩搅拌摩擦焊接头进行一次返修,并对其疲劳试件断口进行SEM扫描与分析。结果表明:返修后焊接接头的疲劳强度低于未返修焊接接头,随着应力的增大,从低应力区到高应力区,两种接头疲劳强度差异缩小;由升降法计算得未返修焊接接头疲劳极限为101.7 MPa,返修接头疲劳极限为75 MPa。断口分析表明:一次返修后疲劳试件未发现明显缺陷,断裂位置主要集中在母材,启裂区表面平滑,扩展二次裂纹少,疲劳纹清晰且粗大,终断区为韧性断口,可观察到大量浅韧窝。
The bobbin tool friction stir welding 6005-T6 aluminum alloy profile joint was repaired once under the same process parameters,and the fracture surfaces of fatigue specimens were analyzed by SEM.The result of SEM scanning showed that,the fatigue strength of welded joints after repairing is lower than that of welded joints without repairing.With the increase of stress,the difference of fatigue strength between the two joints decreases from low stress zone to high stress zone.The fatigue limit of unrepaired welded joint is 101.7 MPa,and the fatigue limit of repaired joint is 75 MPa in lifting fatigue test.The Fracture analysis shows that,there are no obvious defects in the fracture surface of the specimen repaired once.The fatigue fracture position is mainly concentrated in the parent mental zone,the secondary crack propagation is less,the surface of the fracture initiation zone is smooth,and the fatigue beach are clear and gross.A large number of shallow dimples can be observed in the terminal area,which is a ductile toughness fracture.
作者
徐海涛
李静
褚雪峰
陈丽丽
秦志恒
XU Haitao;LI Jing;ZHU Xuefeng;CHEN Lili;QIN Zhiheng(Tangshan Hongzheng Machinery Equipment Co.,Ltd.,Tangshan 064000,China)
出处
《电焊机》
2020年第1期102-104,120,I0010,共5页
Electric Welding Machine
