研究了CO2气体保护焊30Cr Mn Si A高强钢多次补焊对焊缝组织和疲劳性能的影响。结果显示,1次和2次补焊对原焊缝的显微组织和疲劳性能无明显影响,3次补焊后原焊缝晶界处出现块状铁素体,并有少量侧板条状铁素体,这导致3次补焊试样疲劳性能测试数据的分散性变大,且疲劳性能略有减少。同时发现,应力比R数值越大,则各组试样的疲劳寿命增加,而焊缝余高的存在对试样疲劳性能不利。 The effects of multiple welding of CO2 gas shielded welding 30Cr Mn Si A high strength steel on the microstructure and fatigue properties of the weld were investigated. The results show that the primary and secondary weld repairs have no significant effect on the microstructure and fatigue properties of the original weld. The bulk weld appears at the grain boundaries of the original weld after 3 passes, with a few side strips Ferrite, which led to greater scatter in fatigue test data for the three weld repairs and a slight decrease in fatigue properties. It is also found that the larger the stress ratio R is, the longer the fatigue life of each group of specimens is. However, the existence of the remaining weld height is unfavorable to the fatigue properties of the specimens.