| 摘要 |
PURPOSE:To improve the toughness after annealing by combining a wire contg. specific wt% of Si, Mn, Ti, B, Ni, Cr, etc. and flux having prescribed basicity. CONSTITUTION:0.04-0.15% C, 1.30-2.30% Mn, 0.025-0.070% Ti, <=0.45% Si and <=0.0020% B are incorporated as wire components into a titled material. At least >=1 kinds among <=3.80% Ni, <=0.80% Cr, <=0.40% Mo and <=0.80% Cu are further incorporated therein at >=0.20% in the formula (I). The basicity given by the formula (II) is specified to >=1.30 as the flux component and the content of B in both the wire and flux is so controlled as to attain 0.0010-0.0030% when calculated by the formula (III). The content of the Ti and B in the weld metal is thus made adequate by the above-mentioned method and the toughness of the weld meal after stress relief annealing is improved. |
