| 摘要 |
<p>PURPOSE: A high strength structural steel and a manufacturing method thereof are provided to manufacture a structure steel with excellent hydrogen induced cracking resistance and high strength by controlling components such as phosphorus, sulfur, and calcium and a process control. CONSTITUTION: A method for manufacturing a high strength structural steel includes the following steps of: manufacturing a slab comprising carbon, silicone, manganese, phosphorus, sulfur, soluble aluminum, copper, niobium, boron, nickel, chrome, molybdenum, titanium, vanadium, calcium, nitrogen, iron, and unavoidable impurities; reheating the slab at a temperature of 1120-1220°C; cooling the slab after hot-rolling the reheated slab at a temperature of Ar3 or greater; and heat-treating the cooled slab at a temperature of 870-910°C. [Reference numerals] (AA) Start; (BB) End; (S110) Manufacture a steel slab; (S120) Reheat the slab; (S130) Hot rolling; (S140) Cooling (air cooling); (S150) Heat treatment (870-910°C)</p> |
