TMCP TMCP TYPED STEEL AND METHOD OF MANUFACTURING THE SAME

摘要

The present invention provides a thermo-mechanical controlled process (TMCP) steel with an improved impact toughness in a central part and a manufacturing method thereof. According to the present invention, the TMCP steel comprises: 0.06 to 0.085 weight percent of C; 0.15 to 0.25 weight percent of Si; 1.45 to 1.6 weight percent of Mn; 0.01 weight percent or less of P (excluding zero percent); 0.002 weight percent or less of S (excluding zero percent); 0.015 to 0.05 weight percent of Al; 0.15 to 0.25 weight percent of Cu; 0.025 to 0.035 weight percent of Nb; 0.65 to 0.75 weight percent of Ni; 0.01 to 0.1 weight percent of Cr; 0.01 to 0.02 weight percent of Ti; 0.03 to 0.07 weight percent of Mo; 50 ppm or less of N (excluding zero percent); 2.5 ppm or less of H (excluding zero percent); and the balance of Fe and inevitable impurities.