This study investigates the activated flux-tungsten inert gas welding (A-TIG) welding of dissimilar P92 steel-304H ASS using ‘wire feed’ (patent pending) in terms of weld pool mixing behavior, microstructure and mechanical properties of the weld joint. ErNiCrMo-3 wire was fed during welding and three-wire feeding configurations were analyzed in view of filler wire melting and weld pool mixing behavior. The metal from filler wire is transferred into the weld pool in the form of ‘interrupted liquid bridge’ and ‘uninterrupted liquid bridge.’ The ‘uninterrupted liquid bridge’ melting resulted in homogeneous mixing of filler wire into the weld pool. The weld joint produced using the best wire feeding configuration was characterized and compared with the weld joint developed without wire feed. Microstructure alterations were realized with the use of wire feed. The weld zone with wire feed exhibited a fully austenitic structure, whereas; the completely martensitic structure was obtained using A-TIG welding without wire feed. The microstructural transformation led to the improvement of ductility and impact toughness of weld joint without substantial loss of tensile strength. The total elongation and impact toughness of the A-TIG weld joint with wire feed was 45.9% and (89 ± 2) J, respectively, which were significantly higher in contrast to the A-TIG weld joint without wire feed [total elongation: 37.4% and impact toughness: (30 ± 2) J].

这项研究调查了活性焊剂-钨极惰性气体保护焊（在焊接熔池混合行为，焊接接头的显微组织和机械性能方面，使用“送丝”（专利申请中）对不同的P92钢-304H ASS进行A-TIG焊接。在焊接过程中送入了ErNiCrMo-3焊丝，并考虑到填充焊丝熔化和焊池混合行为，对三焊丝送入配置进行了分析。填充焊丝中的金属以“间断液桥”和“不间断液桥”的形式转移到焊池中。“不间断的液桥”熔化导致填充焊丝均匀地混合到焊池中。对使用最佳送丝构型生产的焊接接头进行了表征，并将其与未送丝的焊接接头进行了比较。通过使用送丝可以实现微观结构的改变。带焊丝的焊接区呈现出完全的奥氏体结构，而；使用A-TIG焊接无需送丝即可获得完全马氏体组织。显微组织的转变导致了焊接接头的延展性和冲击韧性的提高，而拉伸强度却没有明显损失。带有送丝的A-TIG焊接接头的总伸长率和冲击韧性分别为45.9％和（89±2）J，与没有送丝的A-TIG焊接接头相比明显更高[总伸长率：37.4 ％和冲击韧性：（30±2）J]。