FILLET WELD JOINT AND METHOD FOR GAS SHIELDED ARC WELDING

摘要

A fillet weld joint of steel having high fatigue strength by improving stress concentration without excessively relying on imparting a compressive residual stress to a toe part by welding materials, free of cracking, and excellent in the toughness, and a method for gas shielded arc welding for obtaining the fillet weld joint are provided. In the fillet weld joint, a martensitic transformation starting temperature (Ms point) of a weld metal is 400°C or above and 550°C or below, a value obtained by dividing a toe radius p of a toe part of welding by a sheet thickness t of a base metal (Á/t) is 0.25 or above, an expression below Ms °C ‰¤ 375 × Á / t + 320
is satisfied, and a crack defect does not exist.