| 摘要 |
<p>The present invention relates to a steel plate having high strength and high toughness, and a method of manufacturing the same. An embodiment of the present invention comprises: 0.05-0.18 wt% of carbon (C), 0.15-0.50 wt% of silicon (Si), 1.00-1.60 wt% of manganese (Mn), 0.01-0.05 wt% of aluminum (Al), 0.10-0.30 wt% of copper (Cu), 0.05-0.25 wt% of nickel (Ni), 0.05-0.25 wt% of chromium (Cr), 0.005-0.03 wt% of niobium (Nb), greater than 0 wt% and 0.015 wt% or less of phosphorus (P), greater than 0 wt% and 0.006 wt% or less of sulphur (S), and the remaining steel plate composed of iron (Fe) and inevitably impurities; and the steel plate has a tensile strength of at least 550 Mpa, a yield strength of at least 415 MPa, and an absorbed energy of at least 200 J (joule) at -50°C.</p> |
