Production mannered null mass of the steel and the production manner and the welding structure where for the welding structure Characteristic of the welding thermal effect

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive welded structure having satisfactory weldability and toughness in an HAZ, and to provide a method for producing the same.;SOLUTION: The steel for an inexpensive welded structure having excellent toughness in the weld heat-affected zone has chemical components comprising, by mass, 0.04 to 0.11% C, 0.02 to 0.30% Si, 1.70 to 2.50% Mn, ≤0.010% P, ≤0.007% S, 0.005 to 0.030% Nb, 0.05 to 0.70% Cu, 0.05 to 0.70% Ni, 0.02 to 0.07% V, 0.0020 to 0.0060% N, ≤0.04% Al, 0.005 to 0.030% Ti, ≤0.0035% Ca and 0.0005 to 0.0030% O, and the balance iron with inevitable impurities, and in which Ceq(M) is higher than 1, Ceq(WES) is 0.48, and Pcm is 0.24.;COPYRIGHT: (C)2009,JPO&INPIT