| 摘要 |
The present invention relates to a high yield ratio-type cold rolled steel sheet having excellent delamination resistance and a crash characteristic; and a manufacturing method thereof. According to the present invention, the high yield ratio-type cold rolled steel sheet comprises: 0.03-0.1 wt% of carbon (C), 0.01-0.35 wt% of silicon (Si), 0.5-1.5 wt% of manganese (Mn), 0.10 wt% or less of phosphorus (P), 0.01 wt% or less of sulfur (S), 0.025-0.07 wt% of aluminum (Sol.Al), 0.003-0.1 wt% of titanium (Ti) and/or 0.003-0.1 wt% of niobium (Nb); and the remainder consisting of iron (Fe) and inevitable impurities, wherein the fine structure has a main structure of ferrite, and an average misorientation angle of the fine structure lies between 16-24°. TiC or NbC precipitations of the fine structure has an average size of 60 nm or less. |
