WELDED JOINT AND WELDED STEEL STRUCTURE HAVING EXCELLENT FATIGUE STRENGTH AND CORROSION RESISTANCE

摘要

PROBLEM TO BE SOLVED: To provide a welded joint and a welded steel structure which have improved fatigue strength and corrosion resistance.;SOLUTION: The welded joint having excellent fatigue strength and corrosion resistance is produced by using a steel sheet comprising, by mass, 0.001 to 0.10% C, 0.1 to 3.0% Si, 0.05 to 3.0% Mn, 0.02 to 0.20% P, ≤0.05% S, 0.001 to 0.1% Al, 0.3 to 3.0% Cr, 0.05 to 1.0% Mo, 0.04 to 1.0% Nb, 0.0001 to 0.01% B and 0.0005 to 0.005% N, and the balance iron with inevitable impurities. The phase having the maximum area ratio in the weld heat affected zone is ferrite, and the average particle diameter thereof is 10 to 30 μm.;COPYRIGHT: (C)2004,JPO