摘要
采用OM、SEM、光谱仪等设备对下摆臂焊合件的焊接接头及母材显微组织、断口显微形貌和材料的化学成分进行了分析,发现焊缝中存在根部裂纹及焊缝边缘存在未熔合缺陷。由于焊接工艺不当,导致下摆臂在焊接接头中形成冷裂纹,在服役应力的作用下,疲劳裂纹扩展,最终导致下摆臂断裂失效。结果表明:通过焊接工艺的改进,增加焊后去应力退火,可降低冷裂纹风险。
Microstructure,fracture morphology and chemical composition of the welded joint of the low arm were analyzed by optical microscope,scanning electron microscopy and spectrometer.It was found that there were root crack in the welding seam and incomplete fusion defects in welding edge.Due to the improper welding process,the cold crack is formed in the welding seam.Under the action of service stress,fatigue cracks propagate,and finally the lower arm breaks.The results show that the risk of cold crack can be reduced by improving welding process and increasing stress relief annealing after welding.
作者
韦贤毅
万永红
蓝先
黄敏鸫
张欢
WEI Xianyi;WAN Yonghong;LAN Xian;HUANG Mindong;ZHANG Huan(SAIC GM Wuling Automobile Co.,Ltd.,Liuzhou Guangxi 545007,China;Administration Commission of Liuzhou Liudong New District,Liuzhou Guangxi 545007,China)
出处
《汽车零部件》
2021年第7期97-99,共3页
Automobile Parts
作者简介
韦贤毅(1991—),男,硕士,工程师,主要从事汽车金属材料性能及应用研究,E-mail:weixianyi3@126.com。
