SUS316L의 파이버 레이저 맞대기 용접 조건에 따른 변형 거동 평가 = Evaluation of Distortion Behavior in SUS316L According to Fiber Laser Butt Welding Conditions

다국어 초록 (Multilingual Abstract)

Fiber laser welding is considered an effective joining process for cryogenic storage structures because of its high welding speed, narrow heat-affected zone, and low thermal deformation. In this study, butt welding was performed on 10 mm-thick SUS316L plates using a fiber laser system, and the distortion behavior according to welding conditions was experimentally evaluated. The main process variables were laser power (4.0 and 4.5 kW) and welding speed (36–54 mm/s), and five welding cases were investigated. Distortion was measured at multiple locations on the welded specimens, and heat input was calculated from laser power and welding speed.
The results showed that, under the 4.0 kW condition, distortion increased as welding speed decreased and heat input increased. At a constant welding speed of 48 mm/s, increasing the laser power from 4.0 kW to 4.5 kW caused a slight increase in distortion. Among all conditions, the 4.5 kW-54 mm/s case showed the largest distortion. In addition, identical heat input conditions did not always produce the same distortion level, indicating that welding distortion was affected not only by heat input but also by the combination of laser power and welding speed. These results provide basic data for the prediction and control of welding distortion in fiber laser butt-welded SUS316L for cryogenic hydrogen storage tank applications.