| 摘要 |
The present invention relates to a high toughness thick steel sheet with improved economical efficiency, high strength, and excellent low-temperature toughness; and a method to manufacture the same. According to an embodiment of the present invention, the high toughness thick steel sheet comprises: 0.03-0.10 wt% of C, 0.01-0.6 wt% of Si, 1.0-2.5 wt% of Mn, 0.01-0.05 wt% of molten Al, 0.01-0.03 wt% of Ti, 0.01-0.06 wt% of Nb, 0.2-0.5 wt% of Cr, 0.01-0.20 wt% of Mo, 0.0003-0.005 wt% of B, more than 0 wt% and 0.015 wt% or less of P, more than 0 wt% and 0.0005 wt% or less of S, and the remainder consisting of Fe and inevitable impurities. Moreover, Cu and Ni are not included. |
