WELDED JOINT OF LOW-ALLOY IRON AND STEEL MATERIAL, WELDING MATERIAL USED FOR THIS WELDED JOIN AND WELDING METHOD FOR WELDED JOINT

摘要

PROBLEM TO BE SOLVED: To provide a welded joint of low-alloy iron and steel materials which is capable of exceedingly improving the fatigue strength of the welded joint even if the welded joint does not undergo toe treatment, quenching treatment or intricate welding method after ordinary welding. SOLUTION: The welded joint is formed by fastening the low-alloy iron and steel materials for structural purposes to each other by welding using welding materials in such a manner that the martensitic transformation initiation temperature of the weld metal formed by welding attains 120 to 400 deg.C and that the coefficient Kt value of stress concentration at the toe of welding attains 1.3 to 2.8.