QUENCHED STEEL SHEET HAVING EXCELLENT HOT PRESS FORMABILITY, AND METHOD FOR MANUFACTURING SAME

摘要

The present invention relates to a quenched steel sheet having excellent hot press formability, and to a method for manufacturing same. The quenched steel sheet according to the present invention comprises: at least one element selected from 0.15-0.30 wt % of carbon (C), 0.05-0.5 wt % of silicon (Si), 1.0-2.0 wt % of manganese (Mn), 0.0005-0.0040 wt % of boron (B), 0.003 wt % or less of sulfur (S), 0.012 wt % or less of phosphor (P), 0.0010-0.0040 wt % of calcium (Ca), and 0.05-1.0 wt % of copper (Cu); at least two elements selected from cobalt (Co), zirconium (Zr), and antimony (Sb); with the remainder being iron and unavoidable impurities. Since the quenched steel sheet of the present invention has enhanced high-temperature ductility by controlling alloying elements, it can be formed at 600 to 900°C through press processing. Therefore, the present invention has the advantages of not only protecting a coating layer, but also of ensuring a tensile strength of 1400 MPa or more and an elongation ratio of 8% or more even after the press processing.