Patent ID: 9394579
Filing Date: 2016-07-19
CPC Classification: C21D,C22C

Claim Text:
1. High-strength steel with good cryogenic temperature toughness, comprising, by weight: 0.01-0.06% of carbon (C), 2.4-8.0% of manganese (Mn), 0.01-6.0% of nickel (Ni), 0.02-0.6% of molybdenum (Mo), 0.03-0.5% of silicon (Si), 0.003-0.05% of aluminum (Al), 0.0015-0.01% of nitrogen (N), 0.02% or less of phosphorous (P), 0.01% or less of sulfur (S), with a remainder of iron (Fe) and other unavoidable impurities, wherein the Mn and Ni satisfy the condition of 8≦1.5×Mn+Ni≦12, and wherein the steel has a yield strength of 500 MPa or more and a cryogenic impact energy of 70 J or more at −196° C. or less.