HIGH STRENGTH STEEL AND METHOD OF MANUFACTURING THE HIGH STRENGTH STEEL

申请公布号：KR20130013562(A)

申请号：KR20110075273

申请日期：2011.07.28

申请公布日期：2013.02.06

申请人：

HYUNDAI STEEL COMPANY

发明人：LEE, SEUNG HA;DO, HYEONG HYEOP;LEE, DONG YUL

分类号：C21D8/02;B21B3/02;C21D9/46;C22C38/00

主分类号：C21D8/02

摘要：PURPOSE: A high strength steel sheet and a manufacturing method thereof are provided to have 440 MPa or more of a tensile strength, 260-310 MPa of a yield point, 35% or more of an elongation, and 0.17 or more of a work hardening exponent by controlling processing conditions and alloy components. CONSTITUTION: A manufacturing method of a high strength steel sheet is as follows. A slab board is composed of 0.14-0.20wt.% of C, 0.01-0.30wt.% of Si, 0.5-1.5wt.% of Mn, 0.01-0.06wt.% of Al, 40ppm or less of V, rest Fe, and inevitable impurities. The slab board is reheated at the 1150-1250°C(S110). The reheated board is hot-rolled at 850-950°C(S120). The hot-rolled board is cooled and wound at 550-650°C(S130). [Reference numerals] (AA) Start; (BB) End; (S110) Slab reheating(SRT: 1150-1250°C); (S120) Hot rolling(FDT: 850-950°C); (S130) Cooling/coiling(CT: 550-650°C)