Austenitic stainless steel
AssigneeArmco Steel Corporation
InventorsGeorge N. Goller, Ronald H. Espy
Life of this patent
Estimating the term…
Abstract
A stress corrosion resistant austenitic stainless steel essentially consisting of from 15.5% to 20% chromium, from 11% to 14% manganese, from 1.1% to 3.75% nickel, from 0.01% to 0.12% carbon, from 0.20% to 0.38% nitrogen, and balance substantially iron. Phosphorous may be present up to 0.06% maximum, sulfur up to 0.04% maximum, and silicon up to 1% maximum. The steel has high strength at room temperature, good stability when severely cold worked, good cryogenic strength and toughness, wear resistance and excellent fusion welding characteristics, making it useful for a multiplicity of cryogenic applications, fabrication of welded articles, and cold-drawn wire.
Claims5
An austenitic stainless steel consisting essentially of from 15.5% to 20% chromium, from 11% to 14% manganese, from 2.50% to 3.75% nickel, from 0.01% to 0.06% carbon, from 0.20% to 0.38% nitrogen, up to 0.06% phosphorus, up to 0.04% sulfur, up to 1% silicon, and remainder substantially iron except for incidental impurities, said steel having an austenite stability factor and a ferrite forming tendency, as hereinbefore defined, falling within the area ABEF of the accompanying graph, exhibiting no stress corrosion failure after 264 hours exposure to boiling magnesium chloride solution, by the hereinbefore described test, and having a Charpy V-notch impact strength of
An austenitic stainless steel consisting essentially of from about 17.50% to about 18.50% chromium, from about 12.25% to about 13.75% manganese, from about 2.75% to about 3.50% nickel, from about 0.03% to about 0.05% carbon, from about 0.23% to about 0.35% nitrogen, up to about 0.04% phosphorus, up to about 0.03% sulfur, from about 0.2% to about 0.7% silicon, and remainder substantially iron except for incidental impurities, said steel having an austenite stability factor and a ferrite forming tendency, as hereinabove defined, falling within the area ABEF of the accompanying graph, exhibiting no stress corrosion failure after 264 hours exposure to boiling magnesium chloride solution, by the hereinbefore described test, and having a Charpy V-notch impact strength of 15 ft-lb minimum at -320.degree.F in the wrought and annealed condition.
An article for cryogenic use exhibiting no stress corrosion failure after 264 hours exposure to boiling magnesium chloride solution, by the hereinbefore described test, and having a Charpy V-notch impact strength of 15 ft-lb minimum at -320.degree.F in the wrought and annealed condition, said article consisting essentially of from 15.5% to 20% chromium, from 11% to 14% manganese, from 2.50% to 3.75% nickel, from 0.01% to 0.06% carbon, from 0.20% to 0.38% nitrogen, up to 0.06% phosphorus, up to 0.04% sulfur, up to 1% silicon, and remainder substantially iron except for incidental impurities.
An austenitic stainless steel consisting essentially of from 17.0% to 17.86% chromium, from 11.88% to 12.79% manganese, from 1.75% to 3.71% nickel, from 0.046% to 0.10% carbon, from 0.23% to 0.38% nitrogen, from 0.39% to 0.52% silicon, and remainder iron except for incidental impurities, said steel having an austenite stability factor and a ferrite forming tendency, as hereinbefore defined, falling within the area ABCD of the accompanying graph, exhibiting no stress corrosion failure after 264 hours exposure to boiling magnesium chloride solution, by the hereinbefore described test, and having a Charpy V-notch impact strength ranging from 17 to 70 ft-lb at -320.degree.F in the hot-worked and annealed condition.
Dependencies are inferred from the claim text.