| 摘要 |
This steel H-beam has a component composition containing C, Si, Mn, Cu, Ni, V, Al, Ti, B, N, and O, and also containing at least one of Mo and Nb. Ceq, calculated with formula (1) below, is 0.37-0.50, the flange plate thickness is 100-150mm, and the area ratio of bainite at the depth position of 1/4 of the flange plate thickness from the outer surface of the flange is 60% or higher. Ceq = C + Mn/6 + (Mo+V)/5 + (Ni+Cu)/15 Formula (1) Here, C, Mn, Mo, V, Ni and Cu are the content of each element. |
