COLD ROLLED STEEL SHEET AND HOT DIP ZINC-BASED PLATED STEEL SHEET HAVING EXCELLENT BAKE HARDENABILITY AND CORROSIONRESISTANCE AND METHOD FOR MANUFACTURING THE SAME

摘要

The present invention relates to a cold rolled steel sheet having an excellent bake hardenability and corrosion resistance, a hot dip zinc-based plated steel sheet, and a method for manufacturing the same. According to the present invention, the cold rolled steel sheet having an excellent bake hardenability and corrosion resistance comprises: one or more selected from a group, including: 0.005-0.08 wt% of C; 1.25 wt% or less of Mn (excluding 0 wt%); 0.03 wt% or less of P (excluding 0 wt%); 0.01 wt% or less of S (excluding 0 wt%); 0.01 wt% or less of N (excluding 0 wt%); 0.01-0.06 wt% of sol.Al; 1.0-2.5 wt% of Cr; 0.1 wt% or less of Sb (excluding 0 wt%); 0.3 wt% or less of Ni (excluding 0 wt%); 0.3 wt% or less of Si (excluding 0 wt%); 0.2 wt% or less of Mo (excluding 0 wt%); 0.003 wt% or less of B (excluding 0 wt%); and residual Fe and other inevitable impurities. The cold rolled steel sheet satisfies the below formula 1. The cold rolled steel sheet additionally comprises: 1-5 area% of martensite; and residual ferrite. [Formula 1] 1.3 = Mn (wt%) + Cr (wt%) / 1.5 + Sb (wt%) = 2.7 (Here, each of Mn, Cr, and Sb means the content (wt%) of each of the elements.)