US 11,788,176 B2
Steel for manufacturing a component by hot forming and use of the component
Jasminko Skrlec, Duisburg (DE); and Stefan Lindner, Willich (DE)
Assigned to OUTOKUMPU OYJ, Helsinki (FI)
Appl. No. 16/482,828
Filed by OUTOKUMPU OYJ, Helsinki (FI)
PCT Filed Feb. 5, 2018, PCT No. PCT/EP2018/052818
§ 371(c)(1), (2) Date Aug. 1, 2019,
PCT Pub. No. WO2018/146050, PCT Pub. Date Aug. 16, 2018.
Claims priority of application No. 17155557 (EP), filed on Feb. 10, 2017.
Prior Publication US 2019/0352755 A1, Nov. 21, 2019
Int. Cl. C22C 38/38 (2006.01); C22C 38/58 (2006.01); C21D 6/00 (2006.01); C21D 9/46 (2006.01); C21D 8/02 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/26 (2006.01); C22C 38/48 (2006.01); C21D 9/08 (2006.01)
CPC C22C 38/58 (2013.01) [C21D 6/002 (2013.01); C21D 8/0205 (2013.01); C21D 8/0247 (2013.01); C21D 9/08 (2013.01); C21D 9/46 (2013.01); C22C 38/001 (2013.01); C22C 38/02 (2013.01); C22C 38/26 (2013.01); C22C 38/38 (2013.01); C22C 38/48 (2013.01); C21D 2211/001 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01)] 12 Claims
 
1. A steel having ductile austenitic areas existing in a martensitic matrix, the steel comprising:
in weight % less than or equal to 0.2%, carbon (C), less than or equal to 3.5% silicon (Si), 3.0-16.0% manganese (Mn), 8.0-14.0% chromium (Cr), less than or equal to 6.0% nickel (Ni), less than or equal to 1.0% nitrogen (N), less than or equal to 1.2% niobium (Nb) linked to the formula Nb=4x(C+N), less than or equal to 1.2% titanium (Ti) so that Ti=4x(C+N)+0.15, and further optionally less than or equal to 2.0% molybdenum (Mo), less than or equal to 0.15% vanadium (V), less than or equal to 2.0% copper (Cu), less than 0.2% aluminum (Al), less than or equal to 0.05% boron (B), the remainder comprising iron and evitable impurities; and
wherein the yield strength of the steel Rp0.2 is in the range of 1100-1350 MPa, the tensile strength of the steel Rm is in the range of 1600-1750 MPa, and the elongation of the steel A40x8 is in the range of 10-12.5%.