Ultra high strength cold rolled steel sheet and method of manufacturing the same

Provided is a cold-rolled steel sheet with ultra-high strength, which has high-strength and high-ductility characteristics. According to one embodiment of the present invention, the cold-rolled steel sheet with ultra-high strength comprises, with respect to 100 wt%, 0.15 to 0.22% of carbon (C), 1.5 to 2.0% of silicon (Si), 2.0 to 3.0% of manganese (Mn), 0.01 to 0.05% of aluminum (Al), 0.01 to 0.05% of titanium (Ti), greater than 0 to 0.015% of phosphorus (P), greater than 0 to 0.005% of sulfur (S), 0.0003 to 0.0015% of boron (B), greater than 0 to 0.006% of nitrogen (N), and the remainder of iron (Fe) and other inevitable impurities. Also, 850 Mpa or more of tensile strength (TS), 1,180 Mpa or more of yield strength (YS), 14% or more of elongation (EL), and 30% or more of hole expandability (HER) are satisfied, and a mixed tissue obtained by mixing ferrite, the reminding austenite, martensite, and bainite is included. 본 발명은, 고강도 및 고연성 특성을 가지는 초고강도 냉연강판을 제공한다. 본 발명의 일 실시예에 의하면, 상기 초고강도 냉연강판은, 중량%로, 탄소(C): 0.15% ~ 0.22%, 실리콘(Si): 1.5% ~ 2.0%, 망간(Mn): 2.0% ~ 3.0%, 알루미늄(Al): 0.01% ~ 0.05%, 티타늄(Ti): 0.01% ~ 0.05%, 인(P): 0% 초과 ~ 0.015%, 황(S): 0% 초과 ~ 0.005%, 보론(B): 0.0003% ~ 0.0015%, 질소(N) 0% 초과 ~ 0.006%, 및 잔부는 철(Fe)과 기타 불가피한 불순물을 포함하고, 항복강도(YP): 850MPa 이상, 인장강도(TP): 1180MPa 이상, 및 연신율(El): 14% 이상, 및 홀확장성(HER): 30% 이상을 만족하고, 페라이트, 잔류 오스테나이트, 마르텐사이트, 및 베이나이트가 혼합된 혼합 조직을 포함한다.