| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-tensile strength fire-resistant steel for a structure which is excellent in high-temperature strength and toughness, in which tensile strength is ≥420 MPa, yield strength at 700°C is ≥50% of the yield strength at room temperature and the Charpy absorbed energy of a base material at -40°C is ≥300 J. <P>SOLUTION: The high-tensile strength fire-resistant steel for a structure comprises, by mass, ≤0.003% C, 0.02 to 0.05% Si, ≤0.10% Al, 0.01 to 1.00% Mn, ≤0.010% P, ≤0.003% S, 0.60 to 1.50% Cr, 0.10 to 0.25% Nb, 0.005 to 0.02% Ti, 0.0005 to 0.0020% B, ≤0.004% N and the balance being Fe and inevitable impurities. <P>COPYRIGHT: (C)2012,JPO&INPIT |
