POSCO Holdings Inc.
High-strength thin steel sheet with excellent drawability and bake hardenability, and method for manufacturing same

Abstract:

A high-strength thin steel sheet having excellent drawability and bake hardenability, and a method of manufacturing the same are provided. The high-strength thin steel sheet includes 0.0005 to 0.003 wt % of carbon (C); 0.5 wt % or less (excluding 0 wt %) of silicon (Si); 1.2 wt % or less (excluding 0 wt %) of manganese (Mn); 0.005 to 0.12 wt % of phosphorous (P); 0.008 wt % or less of sulfur (S); 0.005 wt % or less of nitrogen (N); 0.1 wt % or less (excluding 0 wt %) of acid-soluable aluminum (Al); 0.01 to 0.04 wt % of titanium (Ti); iron (Fe) as a remainder thereof; and unavoidable impurities. The high-strength thin steel sheet has BH of 4 MPa or more and P of 80% or more in Equation 1: P (%)={N.sub.in/(N.sub.in+N.sub.gb)}.times.100, N.sub.in being the number of carbides having a size of 20 nm or less within a crystal grain, and N.sub.gb being the number of carbides having a size of 20 nm or less at a grain boundary.