Over 0.20 Percent Nitrogen Containing Patents (Class 420/59)
  • Patent number: 4824636
    Abstract: Austenitic steel with improved high-temperature strength and corrosion resistance, characterized by the simultaneous presence, in defined quantities, of Nb, Mo and V and by the presence of C and N in a specific ratio with said three elements.
    Type: Grant
    Filed: March 5, 1987
    Date of Patent: April 25, 1989
    Assignee: Centro Sviluppo Materiali S.p.A.
    Inventors: Sergio Vacchiano, Giovanni Lanfranco, Roberto Gubiotti
  • Patent number: 4822556
    Abstract: A nonmagnetic austenitic stainless steel and articles such as drill collars or boat shafts fabricated therefrom, the steel having a 0.2% yield strength of at least 100 ksi (689 N/mm.sup.2), improved resistance to intergranular stress corrosion, good ductility, good corrosion resistance and low magnetic permeability, and consisting essentially of, in weight percent, from greater than 0.05% to about 0.10% carbon, greater than 14% to about 18% manganese, about 15% to about 20% chromium, about 1% to about 3.5% nickel, about 0.3% to about 0.55% nitrogen, about 0.10% to about 0.5% vanadium, about 1.0% maximum copper, about 1.0% maximum molybdenum, about 1.0% maximum silicon, about 0.04% maximum phosphorous, about 0.03% maximum sulfur, and balance essentially iron.
    Type: Grant
    Filed: February 26, 1987
    Date of Patent: April 18, 1989
    Assignee: Baltimore Specialty Steels Corporation
    Inventors: James N. Cordea, Joseph C. Jasper, Harshad V. Sheth
  • Patent number: 4814140
    Abstract: A galling and corrosion resistant austenitic stainless steel alloy is disclosed containing in weight percent about______________________________________ w/o ______________________________________ Carbon 0.25 Max. Manganese 2.0-7.0 Silicon 1.0-5.0 Phosphorus 0.05 Max. Sulfur 0.3 Max. Chromium 12-20 Nickel 2.0-7.75 Molybdenum 3 Max. Copper 3 Max. Nitrogen 0.35 Max. ______________________________________the balance being essentially iron. To attain its unique properties the alloy must be balanced so as to contain no more than about 10% ferrite. The % Ni+1/2(% Mn) must not be less than 5.5% and not greater than 1/8[11(% Si)+42], and the sum of the (% C+% N) is at least 0.15%. Care must be taken that when the amount of silicon present is less than about 2.25%, at least about 4.0% manganese is present.
    Type: Grant
    Filed: June 16, 1987
    Date of Patent: March 21, 1989
    Assignee: Carpenter Technology Corporation
    Inventor: John H. Magee, Jr.
  • Patent number: 4803045
    Abstract: Novel wear-resistant, anti-galling, cobalt-free hardfacing iron based alloys are provided which are useful for construction of plant or manufacturing facility components exposed to aggressive environments. The alloys are particularly useful to construct components used in the cooling systems of nuclear power plants.
    Type: Grant
    Filed: October 24, 1986
    Date of Patent: February 7, 1989
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Evan K. Ohriner, Edward P. Whelan, Tsuguyasu Wada, Howard Ocken
  • Patent number: 4765953
    Abstract: According to the invention there is a high nitrogen containing duplex stainless steel with high corrosion resistance and good structure stability. Characteristic is the analysis of the alloy being in % by weight max 0.05% C, 23-27% Cr, 5.5-9.0% Ni, 0.25-0.40% N, max 0.8% Si, max 1.2% Mn, 3.5-4.9% Mo, max 0.5% Cu, max 0.5% W, max 0.010% S, max 0.5% V, max 0.18% Ce and Fe and normally present impurities, at which the contents of the alloying elements are so adjusted that the ferrite content after solution heat treatment at about 1075.degree. C. amounts to 30-55%. The analysis of the steel is so optimized that it in solution heat treated, cold worked and also welded condition is particularly suitable for use in such environments where the presence of chloride ions gives rise to a high corrosivity.
    Type: Grant
    Filed: September 5, 1986
    Date of Patent: August 23, 1988
    Assignee: Santrade Limited
    Inventors: Carl P. U. Hagenfeldt, Sven-Olof Bernhardsson, Erik V. S. Lagerberg
  • Patent number: 4754950
    Abstract: There is disclosed a valve comprising one valve seat ring, of a disc or a body, having a surface composed of a Cr-Mn-Fe system or a Cr-Ni-Fe system Fe-based precipitation hardening type alloy, and another valve seat ring thereof having a surface composed of a Cr-Ni system Ni-based alloy having a hardness Hv of 400 or more.The valves of this invention can have excellent wear resistance, cavitation erosion resistance and galling resistance, and since emitting no cobalt, the valves of this invention are suitable for various plants such as chemical plants, particularly nuclear power plants.
    Type: Grant
    Filed: October 29, 1985
    Date of Patent: July 5, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kaoru Tada, Mituo Kawai, Tetsuo Fujiwara, Noriyuki Chujyo, Masahiko Hasunuma, Yuji Yasuda
  • Patent number: 4721600
    Abstract: A superplastic hot working method for a duplex-phase, nitrogen-containing ferrous alloy and stainless steel, and a superplastic duplex-phase ferrous alloy are disclosed. The ferrous alloy comprises: at least one of Si and Mn in an amount of not less than 0.5% and not less than 1.7%, respectively; and N: at least 0.01% in solid solution, wherein Si eq and Mn eq which are defined as:Si eq=Si+(2/3)(Cr+Mo), and Mn eq=Mn+2 Ni+60 C+50 N,satisfy the formula:(5/6)(Si eq)-15/2.ltoreq.Mn eq.ltoreq.(11/5)(Si eq)-77/5,and its superplastic hot working is carried out by deforming the alloy heated to 700.degree.-1200.degree. C. at a strain rate of 1.times.10.sup.-6 S.sup.-1 to 1.times.10.sup.0 S.sup.-1. In another aspect, superplastic hot working of a duplex-phase stainless steel comprising Cr: 10.0-35.0%, Ni: 2.0-18.0%, Mo: 0-6.0%, and N: 0.005-0.3% and having the values of Si eq and Mn eq as above is carried out by deforming the steel at a strain rate of from 1.times.10.sup.-6 S.sup.-1 to 1.times.10.sup.1 S.sup.
    Type: Grant
    Filed: March 27, 1986
    Date of Patent: January 26, 1988
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Yasuhiro Maehara, Yoshio Tarutani
  • Patent number: 4689198
    Abstract: Disclosed herein is a high strength austenitic stainless steel with excellent corrosion resistance even in oxidative enviroments, and a method for producing such stainless steel, in which the kinds and proportions of the component elements are strictly restricted, especially limiting the contents of C and N to achieve solution strengthening while preventing degradations in corrosion resistance and defects of steel ingots which would be caused if they are added excessively. Besides, V is added under coexistence with Cr and Ni to increase the strength by precipitation of carbides and nitrides of V while preventing production of Cr carbides.
    Type: Grant
    Filed: October 3, 1985
    Date of Patent: August 25, 1987
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Kazuo Fujiwara, Yasushi Torii, Koujiro Kitahata, Tsuyoshi Inoue, Tadamasa Yokoyama, deceased
  • Patent number: 4675156
    Abstract: Disclosed is a structural austenitic stainless steel with superior proof stress and toughness at cryogenic temperatures. The steel has a composition essentially consisting of, by weight, not greater than 0.05% of carbon, 0.20 to 0.70% of nitrogen, not greater than 1.0% of silicon, not greater than 25% of manganese, 13 to 35% of chromium, 5 to 25% of nickel and the balance substantially iron. The chromium content and manganese content is selected to meet the condition of (Cr+0.9 Mn).gtoreq.20%. The index of cleanliness showing the amount of nonmetallic inclusions is not greater than 0.1%.
    Type: Grant
    Filed: August 15, 1985
    Date of Patent: June 23, 1987
    Assignees: Nippon Steel Corporation, Japan Atomic Energy Research Institute
    Inventors: Setsu Sakamoto, Yasuhiro Nakagawa, Isamu Yamauchi, Takashi Zaizen, Katsumi Suzuki, Susumu Shimamoto, Hideo Nakajima
  • Patent number: 4640817
    Abstract: A dual-phase stainless steel exhibiting improved resistance to corrosion caused by nitric acid is disclosed, which consists essentially of:C: not more than 0.02% by weight, Si: 2-6% by weight,Mn: 0.1-2% by weight, Cr: 20-35% by weight,Ni: 3-27% by weight, P: not more than 0.02% by weight,N: not more than 0.30% by weight,Fe and incidental impurities: balance the amount of ferrite to be 30-70% by volume.
    Type: Grant
    Filed: July 27, 1984
    Date of Patent: February 3, 1987
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Haruhiko Kajimura, Hiroo Nagano, Minoru Miura
  • Patent number: 4609577
    Abstract: A method of producing a weld overlay on a ferrous base metal surface, by applying to the surface by electric arc welding a plurality of layers of an austenitic stainless steel filler of specific composition, and providing a flux which produces a substantially fully austenitic overlay at least in the uppermost layer. The overlay has improved machinability, metal-to-metal wear resistance and corrosion resistance, and the capability of work hardening.
    Type: Grant
    Filed: January 10, 1985
    Date of Patent: September 2, 1986
    Assignee: Armco Inc.
    Inventor: W. Herbert Long
  • Patent number: 4337089
    Abstract: Copper-nickel-tin alloys having high tensile strength and conductivity suitable for lead conductor materials for integrated circuits are produced by melting a starting material containing 0.5-3.0% by weight of Ni, 0.3-0.9% by weight of Sn, 0.01-0.2% by weight of phosphorus and 0-0.35% by weight of at least one of Mn and Si other than Cu, casting the molten metal, rolling conventionally the cast into a sheet having a thickness corresponding to more than 60% of cold reduction rate of the final necessary gauge, annealing such a rolled sheet at a temperature of 300-395.degree. C. for 1 hour, cold rolling the annealed sheet and annealing the cold rolled sheet at a temperature of 150-250.degree. C. for 1 hour.
    Type: Grant
    Filed: December 29, 1980
    Date of Patent: June 29, 1982
    Assignees: Nippon Telegraph and Telephone Public Corporation, Nippon Bell Parts Co., Ltd., Nihon Telecommunication Engineering Corporation
    Inventors: Kishio Arita, Kiyoshi Murakawa, Toshio Takahashi