To provide a welded joint of soft steel and steel in a 490 MPa class having fatigue strength more excellent than that of the conventional one though the introduction of compressive stress into the toes of weld utilizing the transformation expansion of weld metal in them has been difficult compared with the case of strength steel.
In the welded joint of soft steel or steel in a 490 MPa class having excellent fatigue strength, the weld beads of the toes of weld are formed with additional weld beads composed of weld metal having chemical components containing, by mass, 0.02 to 0.1% C, 0.1 to 0.7% Si, 0.1 to 1.5% Mn, ≤0.03% P, ≤0.02% S, 13 to 16% Cr and 10 to 13% Ni, and the balance iron with unavoidable impurities, and whose temperature at which transformation starts from austenite into martensite is 125 to 200°C.
MIZUMOTO MANABU
NAKAJIMA KIYOTAKA
TOMINAGA NORIYOSHI
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