Patent ID: 6451134
Filing Date: 2002-09-17
Classification: B21B,C21D,C22C

Abstract:
A 590 MPa class heavy gauge H-shaped steel with excellent as-rolled toughness in the direction of the flange thickness, comprising 0.001 to 0.025 wt % of C, 0.6 wt % or less of Si, 0.4 to 1.6 wt % of Mn, 0.025 wt % or less of P, 0.010 wt % or less of S, 0.1 wt % or less of Al, 0.6 to 2.0 wt % of Cu, 0.25 to 2.0 wt % of Ni, 0.001 to 0.050 wt % of Ti, 0.0002 to 0.0030 wt % of B, 0.05 to 0.5 wt % of Cr, one or two of 0.030 wt % or less of REM and 0.0100 wt % or less of Ca, and at least one of 0.5 wt % or less of Mo, 0.10 wt % or less of V, and 0.10 wt % or less of Nb, wherein Mn/Cu&lE;2.0 and&lE;250&lE;117 Mn (wt %)+163 Cu (wt %)&lE;350 are satisfied.