High-strength reinforcing steel and method for manufacturing same

A method for manufacturing a high-strength steel bar, comprising the steps of:

• (a) reheating a steel slab at a temperature ranging from 1000° C. to 1100° C., the steel slab comprising, by weight %:
• 0.18% to 0.45% carbon (C);
• 0.05% to 0.30% silicon (Si);
• 0.40% to 3.00% manganese (Mn);
• greater than 0% and not more than 0.04% phosphorus (P);
• greater than 0% and not more than 0.04% sulfur (S);
• greater than 0% and not more than 1.0% chromium (Cr);
• greater than 0% and not more than 0.50% copper (Cu);
• greater than 0% and not more than 0.25% nickel (Ni);
• greater than 0% and not more than 0.50% molybdenum (Mo);
• greater than 0% and not more than 0.040% aluminum (Al);
• greater than 0% and not more than 0.20% vanadium (V);
• greater than 0% and not more than 0.040% nitrogen (N);
• greater than 0% and not more than 0.1% antimony (Sb);
• greater than 0% and not more than 0.1% tin (Sn);
• and the balance of iron (Fe) and other inevitable impurities;
• (b) finish hot-rolling the reheated steel slab at a temperature of 850° C. to 1000° C.;
• and
• (c) cooling the hot-rolled steel to a martensite transformation start temperature (Ms (° C.)) through a tempcore process.