Elemental segregation leads to hot fissuring in the Incoloy 20. The present investigation examines the possibility of lessening the elemental segregation in the conventional arc welding techniques. In the present investigation, Incoloy 20 plates were fused by continuous current gas tungsten arc welding (CCGTAW) and pulsed current gas tungsten arc welding (PCGTAW) with two different nickel-based filler wires (ERNiCrMo-2 and ERNiCrMo-3). The result of the macroexamination shows that steady fluid flow with crack-free welding was succeeded in all the weldments. Optical and scanning electron microscope proves the columnar and cellular structure in CCGTAW specimens and fine equiaxed dendritic structure in PCGTAW specimens. Energy-dispersive spectroscopy (EDS) and X-ray diffraction results exhibit that the weld joint produced by CCGTAW ERNiCrMo-2 shows Cr segregation that leads to the formation of M₂₃C₆ phases in the interdendritic regions, whereas ERNiCrMo-3 shows the presence of NbC instead of M₂₃C₆. The elemental segregation is suppressed when it comes to PCGTA weldments in both filler wires. Electron backscatter diffraction analysis shows that the CCGTA weldments show coarser grain structure in the heat-affected zone (HAZ). In all the cases, the formation of secondary phases affects the strength of the weld joints at HAZ. Refined microstructure obtained in the PCGTAW in both filler wires shows the marginally higher ultimate tensile strength and toughness compared to the corresponding CCGTA weldments. From the corrosion study, PCGTAW specimens exhibit higher corrosion resistance than the CCGTAW specimens for both filler wires.

元素偏析导致Incoloy 20中的热裂变。本研究调查了在常规电弧焊技术中减轻元素偏析的可能性。在本研究中，Incoloy 20板通过使用两种不同的镍基填充焊丝（ERNiCrMo-2和ERNiCrMo-3）的连续电流钨极电弧焊（CCGTAW）和脉冲电流钨极电弧焊（PCGTAW）进行熔化。宏观检查的结果表明，在所有焊件上都成功实现了无裂纹焊接的稳定流体流动。光学和扫描电子显微镜证明了CCGTAW标本的柱状和细胞结构以及PCGTAW标本的细等轴树状结构。在树突间区域中存在₂₃ C ₆相，而ERNiCrMo-3显示存在NbC而不是M ₂₃ C ₆。当涉及两条填充焊丝中的PCGTA焊件时，元素偏析得到抑制。电子背散射衍射分析表明，CCGTA焊件在热影响区（HAZ）的晶粒组织较粗。在所有情况下，次级相的形成都会影响热影响区的焊接接头强度。与相应的CCGTA焊件相比，在PCGTAW中在两条填充焊丝中获得的细化微观结构均显示出略高的极限抗拉强度和韧性。从腐蚀研究来看，对于两种填充焊丝，PCGTAW试样均具有比CCGTAW试样更高的耐腐蚀性。