CAJ | 학술논문

采用熔焊填充+搅拌摩擦补焊复合工艺成功进行了搅拌摩擦焊缝匙孔型缺陷的修补，焊后对补焊接头的微观组织和力学性能进行了分析。结果表明，焊核区呈细小的再结晶等轴晶粒，热机影响区发生粗化长大，逐渐丧失了原始母材轧制晶粒边界形貌，并残留熔焊柱状晶或树枝状晶粒。第二相析出物粗化长大，呈网状结构分布于热机影响区域。热影响区/热机影响区是整个补焊接头的薄弱环节，拉伸试样亦断裂在该区域。补焊接头断口呈现出韧性断裂与铸态组织脆性断裂的混合断口形貌。
채용용한전충+교반마찰보한복합공예성공진행료교반마찰한봉시공형결함적수보，한후대보한접두적미관조직화역학성능진행료분석。결과표명，한핵구정세소적재결정등축정립，열궤영향구발생조화장대，축점상실료원시모재알제정립변계형모，병잔류용한주상정혹수지상정립。제이상석출물조화장대，정망상결구분포우열궤영향구역。열영향구/열궤영향구시정개보한접두적박약배절，랍신시양역단렬재해구역。보한접두단구정현출인성단렬여주태조직취성단렬적혼합단구형모。
The composite process of fusion ifll-ing + friction stir repaired welding has been successfully used to repair the keyhole defect, and the microstructure and mechanical properties of the repaired joint have been analyzed. The microstructure of the TMAZ coarsens and grows up with the boundary morphology of the original parent metal gradually disappearing, and even there is part of columnar or dendrite crystals from the fusion filling process existing in the TMAZ. SEM observation shows that the precipitated phase in the TMAZ also coarsens and grows up with the network structure distributed. The re-sults of microhardness and tensile test present the inhomo-geneous mechanical behavior of the repaired joint. TMAZ is the weak link of the repaired joint, and the tensile speci-men also fractures in this zone. The fracture morphology shows the ductile fracture in the nugget zone and brittle fracture in the TMAZ.