A Study on Process Robustness of Lap Joint Fillet Welding in GTAW Using C Type Filler

Thin plate stainless steel is mainly used for lap joint fillet welding in GTAW and GMAW pro- cesses. However, due to the machining tolerance of the product, gaps are generated, and the weld line of the product before welding is not consistent. As a result, welding defects such as burn through and discontinuous bead frequently occur. If C-Filler is used for lap joint fillet welding with GTAW, the gap bridging ability is improved compared to rod-type filler due to the wide C-Filler, and it is expected that it will be possible to prevent weld defect even if the weld line is not consistent. In this study, we examined the molten pool flow ahead of the arc by changing the push angle, inclined downward angle and deposition area in lap joint fillet welding. We also increased the gap and moved the weld line to test the process robustness. Key words: GTAW, C-Filler, Lap joint fillet welding, Seam leave, Gap bridging, High speed welding