| 摘要 |
The present invention provides a high strength steel having superior brittle crack arrestability and a method for manufacturing the same. According to the present invention, the high strength steel having superior brittle crack arrestability comprises: 0.05-0.1 wt% of carbon (C); 1.5-2.2 wt% of manganese (Mn); 0.3-1.2 wt% of nickel (Ni); 0.005-0.1 wt% of niobium (Nb); 0.005-0.1 wt% of titanium (Ti); 0.1-0.5 wt% of copper (Cu); 0.1-0.3 wt% of silicon (Si); 100 ppm or less of phosphorus (P); 40 ppm or less of sulfur (S); and the remaining consisting of iron (Fe) and inevitable impurities. Moreover, the high strength steel having superior brittle crack arrestability has a microstructure including one structure selected from a group consisting of a ferrite monolithic structure, a bainite monolithic structure, a ferrite and bainite combined structure, a ferrite and pearlite combined structure and a ferrite, bainite and pearlite combined tissue in a thickness of 50 mm or more. According to the present invention, a high strength steel with superior brittle crack arrestability as well as high yield strength and superior Charpy impact transition temperature can be obtained. |
