METHOD FOR MANUFACTURING HOT-ROLLED STEEL HAVING EXCELLENT CORROSION RESISTANCE PROPERTY AND THE HOT-ROLLED STEEL BY THE SAME METHOD

摘要

PURPOSE: A hot-rolled steel sheet having excellent corrosion resistance properties and a manufacturing method thereof are provided to improve a folding resistance and a corrosion resistance by optimizing a steel component and a manufacturing process etc. CONSTITUTION: A hot-rolled steel sheet having excellent corrosion resistance properties comprises the following steps: a hot-rolled steel sheet is manufactured with a steel containing 0.001-0.005% of carbon (C), 0.05-0.3% of manganese (Mn), 0.01-0.020% of phosphorus (P), less than 0.020% (0% exclusion) of sulfur (S), 0.01-0.07% of aluminum (Al), 0.001-0.004% of nitrogen (N), 0.0005-0.002% of boron (B), 0.05-0.5% of copper (Cu), 0.01-0.05% of vanadium (V), and a rest iron (Fe) and other unavoidable impurities by a weight%; a shot ball of which the size is 0.10-0.40 mm is short-blasted at 40-65 m/sec on the hot-rolled steel sheet; and each component of the steel is satisfied with 0.3=(B(%)/11)/(N(%)/14)=1.0, 8=(Cu(%)/64)/(S(%)/32)=25, and 1.2= (V(%)/51)/(C(%)/12)=3.0 respectively. [Reference numerals] (AA) Evaluation value (fluting index & processability); (BB) Fluting index; (CC) Processability; (DD) Illumination index ratio (Rmax/Ra)