| 摘要 |
PROBLEM TO BE SOLVED: To provide a martensitic stainless steel welding structural body in which fire resistance is imparted as the whole of the building structure. SOLUTION: This structural body is composed of a martensitic stainless steel base material having a composition containing, by mass, 0.005 to 0.1% C, <=0.50% Si, <=1.5% Mn, <=0.030% P, <=0.0050% S, 10.0 to 15.0% Cr, 0.5 to 6.0% Ni, 0.3 to 3.0% Mo, <=0.03% N, <=0.15% Al and 0.003 to 0.050% Ti, in which the content of Ni and the content of Mo satisfy the relation in the inequality (1), and the balance Fe with inevitable impurities, and whose proof stress at 600 deg.C is >=2/3 to the cold proof stress and a weld metal containing components within the ranges same as those of the base material, and in which the B value and C value in formulae (2) and (3) respectively lie in the ranges of 14.0 to 17.0 and >=-11.8: A=[Mo]-4.41[Ni]+22.94>=0...(1), B=[Ni]+0.5[Mn]+30[C]+0.8[Cr]+0.8[Mo]+1.2[Si]...(2), and C=[Ni]+0.5[Mn]+30[C]-1.1[Cr]-1.1[Mo]-1.6[Si]...(3). |
