Influence of Induction Heating on Thermal Characteristics and Residual Stress for Plasma Arc Welding of Structural Steel Plate

Structural steels are widely adopted in offshore structures, high-rise buildings, bridges, storage tanks, and construction machines because of their low cost and toughness. However, structural steels are encountered various problems, such as cracking, residual stress and distortion during the arc welding process, leading to early failure of the weld joint. Currently, a finite element-based analysis is conducted by adopting a high-frequency induction heating (HFIH) source as a preheat source to relieve the residual stresses. HFIH is a non-contact, environmentally friendly heating process suitable for the scanning heating of the weld line. The present study finds that the addition of HFIH significantly affects the final residual stress distribution and improves the weld penetration.