With Working Patents (Class 148/609)
  • Publication number: 20100122754
    Abstract: A high-strength martensite heat resisting steel which has long-time creep rupture strength required for steam temperature condition of 600-630° C. and toughness at room temperature, and which is suitable for use as a material of a steam turbine rotor shaft and as large-sized forged steel with an improvement of hot forgeability. A method of producing the steel and applications of the steel are also provided. The high-strength martensite heat resisting steel contains 0.05-0.20% by mass of C, 0.1% or less of Si, 0.05-0.6% of Mn, 0.1-0.6% of Ni, 9.0-12.0% of Cr, 0.20-0.65% of Mo, 2.0-3.0% of W, 0.1-0.3% of V, 2.0% or less of Co, 0.02-0.20% of Nb, 0.015% or less of B, 0.01-0.10% of N, and 0.015% or less of Al, (W/Mo) being 4.0-10.0.
    Type: Application
    Filed: September 28, 2006
    Publication date: May 20, 2010
    Inventors: Hirotsugu Kawanaka, Masahiko Arai, Hideo Yoda
  • Patent number: 7708841
    Abstract: An austenitic, substantially ferrite-free steel alloy and a process for producing components therefrom. This Abstract is not intended to define the invention disclosed in the specification, nor intended to limit the scope of the invention in any way.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: May 4, 2010
    Assignees: Boehler Edelstahl GmbH & Co KG, Schoeller-Bleckmann Oilfield Technology GmbH
    Inventors: Gabriele Saller, Herbert Aigner, Josef Bernauer, Raimund Huber
  • Publication number: 20100096048
    Abstract: A martensitic stainless steel for inexpensive seamless pipe having 655 MPa yield strength, high toughness and excellent corrosion resistance in high CO2 environments, and a method for manufacturing thereof is provided. The steel comprises C: 0.005-0.05%, Si: 0.1-0.5%, Mn: 0.1-2.0%, P: ?0.05%, S: ?0.005%, Cr: 10.0-12.5%, Mo: 0.1-0.5%, Ni: 1.5-3.0%, N: ?0.02%, Al: 0.01-0.1%, by weight, while FI value defined by the formula [FI=Cr+Mo?Ni?30(C+N)] being 5.00 to 8.49, and balance of substantially Fe. The method comprises the steps of reheating the cooled steel at temperatures from 780° C. to 960° C., quenching the reheated steel, and then tempering the quenched steel at temperatures from 550° C. to 650° C.
    Type: Application
    Filed: December 30, 2009
    Publication date: April 22, 2010
    Applicant: NKKTUBES
    Inventors: Shuji Hashizume, Yusuke Minami, Tatsuo Ono
  • Publication number: 20100000636
    Abstract: The invention relates to a duplex stainless steel composition, the composition of which consists of, in % by weight: C?0.05% 21%?Cr?25% 1%?Ni?2.95% 0.16%?N?0.28% Mn?2.0% Mo+W/2?0.50% Mo?0.45% W?0.15% Si?1.4% Al?0.05% 0.11%?Cu?0.50% S?0.010% P?0.040% Co?0.5% REM?0.1% V?0.5% Ti?0.1% Nb? 0.3% Mg?0.1% the balance being iron and impurities resulting from the smelting, and the microstructure consisting of austenite and 35 to 65% ferrite by volume, the composition furthermore satisfying the following relationships: 40?IF?70 where IF=6×(% Cr+1.32×% Mo+1.27×% Si)?10×(% Ni+24×% C+16.15×% N+0.5×% Cu+0.4×% Mn)?6.17 and ILCR?30.5 where ILCR=% Cr+3.3×% Mo+16×% N+2.6×% Ni?0.7×% Mn, and also to a process for manufacturing plate, strip, coil, bar, rod, wire, sections, forgings and castings made of this steel.
    Type: Application
    Filed: June 15, 2007
    Publication date: January 7, 2010
    Applicants: INDUSTEEL CREUSOT, UGITECH
    Inventors: Bernard Bonnefois, Jerome Peultier, Mickael Serriere, Jean-Michel Hauser, Eric Chauveau
  • Publication number: 20090301615
    Abstract: The invention concerns a method for making a unitary spark ignition valve, characterized in that it consists in preparing and casting a steel made up in wt. % of: 0.45%?C 0.55%; 12%?Cr?18%; 1%?Si?2.5%; traces?Mn?2%; 0.2%?V?0.5%; traces?Mo?0.5%; 0.05%?N?0.15% with 0.55%?C+N?0.70%; traces?Ni?1%; traces?Cu?0.25%; or Cu?0.5 Ni if Cu>0.25%; traces?Co?1%; traces?W?0.2%; traces?Nb?0.15%; traces?AI?0.025%; traces?Ti?0.010%; traces?S?0.030%; traces?P?0.040%; traces?B?0.0050%; the balance being iron and impurities resulting from the preparation; in transforming by hot thermomechanical process, for example, by rolling and/or forging between 1000 and 1200° C.; optionally soft annealing, between 650 and 900° C.
    Type: Application
    Filed: January 22, 2007
    Publication date: December 10, 2009
    Inventor: Jacques Montagnon
  • Publication number: 20090252640
    Abstract: A steel alloy is described that, in weight-%, includes 0.08-0.19 C, where 0.16?C+N?0.28, 0.1-1.5 Si, 0.1-2.0 Mn, 13.0-15.4 Cr, 0.01-1.8 Ni, 0.01-1.3 Mo, max. 0.7 V, max. 0.25 S, max. 0.01 Ca, max. 0.01 O, in order to improve the machinability of the steel, and balance iron and unavoidable impurities, wherein the steel alloy has a microstructure which, in a tough hardened condition, comprises a martensitic matrix with up to 30 vol-% ferrite.
    Type: Application
    Filed: February 2, 2007
    Publication date: October 8, 2009
    Applicant: UDDEHOLM TOOLING AKTIEBOLAG
    Inventors: Odd Sandberg, Magnus Tidesten, Thomas Hillskog
  • Publication number: 20090184790
    Abstract: A soft magnetic alloy consists essentially of 5 percent by weight?Co?30 percent by weight, 1 percent by weight?Cr?20 percent by weight, 0.1 percent by weight?Al?2 percent by weight, 0 percent by weight?Si?1.5 percent by weight, 0.017 percent by weight?Mn?0.2 percent by weight, 0.01 percent by weight?S?0.05 percent by weight where Mn/S is >1.7, 0 percent by weight?O?0.0015 percent by weight, und 0.0003 percent by weight?Ce?0.05 percent by weight, 0 percent by weight?Ca?0.005 percent by weight and the remainder iron, where 0.117 percent by weight?(Al+Si+Mn+V+Mo+W+Nb+Ti+Ni)?5 percent by weight.
    Type: Application
    Filed: July 24, 2008
    Publication date: July 23, 2009
    Applicant: Vacuumschmelze GmbH & Co. KG
    Inventors: Witold Pieper, Joachim Gerster
  • Publication number: 20090165905
    Abstract: A ferritic stainless steel sheet has a composition of C up to 0.02 mass %, Si up to 0.8 mass %, Mn up to 1.5 mass %, P up to 0.050 mass %, S up to 0.01 mass %, 8.0-35.0 mass % of Cr, N up to 0.05 mass %, 0.05-0.40 mass % of Ti and 0.10-0.50 mass % of Nb with a product of (% Ti % N) less than 0.005. Precipitates of 0.15 ?m or more in particle size except TiN are distributed in a steel matrix at a rate of 5000-50000/mm2. The steel sheet is manufactured by hot-rolling a slab at a finish-temperature of 800° C. or lower, annealing the hot-rolled steel sheet at 450-1080° C., cold-rolling the hot-rolled steel sheet in accompaniment with intermediate-annealing at a temperature within a range of from (a recrystallization-finishing temperature ?100° C.) to (a recrystallization-finishing temperature) and then finish-annealing the cold-rolled steel sheet at 1080° C. or lower.
    Type: Application
    Filed: March 3, 2009
    Publication date: July 2, 2009
    Applicant: Nisshin Steel Co., Ltd.
    Inventors: Yasutoshi Hideshima, Kouki Tomimura, Naoto Hiramatsu
  • Publication number: 20090098009
    Abstract: The present invention provides optimal low chromium stainless steel preventing the deterioration in corrosion resistance at the weld zone in the case of multipass welding, superior in grain boundary corrosion resistance of the weld zone even in a harsh corrosive environment, simultaneously free from preferential corrosion at the heat affected zones near weld fusion lines, and further superior in manufacturability, that is, low chromium stainless steel containing, by mass %, C: 0.03% or less, N: 0.004 to 0.02%, Si: 0.2 to 1%, Mn: over 1.5 to 2.5%, P: 0.04% or less, S: 0.03% or less, Cr: 10 to 15%, Ni: 0.2 to 3.0%, and Al: 0.005 to 0.1%, further containing Ti: 4×(C %+N %) to 0.35%, and having a balance of Fe and unavoidable impurities, having a ?p(%) expressed by a predetermined formula satisfying 80 or more, and satisfying Ti %×N %<0.004 as well.
    Type: Application
    Filed: July 3, 2007
    Publication date: April 16, 2009
    Inventors: Masuhiro Fukaya, Akihiko Takahashi, Shinichi Teraoka, Shunji Sakamoto
  • Patent number: 7494551
    Abstract: A Ti-containing ferritic stainless steel sheet and a manufacturing method thereof include stainless steels being formed while a refining load is decreased and having a low yield strength which exhibits superior workability. The Ti-containing ferritic stainless steel sheet contains on mass percent basis: 0.01% or less of C; 0.5% or less of Si; 0.3% or less of Mn; 0.01% to 0.04% of P; 0.01% or less of S; 8% to 30% of Cr; 1.0% or less of Al; 0.05% to 0.5% of Ti; 0.04% or less of N, 8?Ti/(C+N)?30 being satisfied; and the balance being substantially Fe and incidental impurities, wherein a grain size number of ferrite grain is 6.0 or more, and an average diameter Dp of precipitation diameters, each being [(a long axis length of a Ti base precipitate+a short axis length thereof)/2], of the Ti base precipitates in the steel sheet is in the range of from 0.05 ?m to 1.0 ?m.
    Type: Grant
    Filed: June 16, 2003
    Date of Patent: February 24, 2009
    Assignee: JFE Steel Corporation
    Inventors: Yoshihiro Yazawa, Osamu Furukimi, Yasushi Kato
  • Patent number: 7475478
    Abstract: A method for making structural automotive components and the like includes providing a blank of air hardenable martensitic stainless steel in the annealed condition. The steel blank has a thickness in the range of 0.5-5.0 mm., and is formed utilizing stamping, forging, pressing, or roller forming techniques or the like into the form of an automotive structural member. The automotive structural member is then hardened by application of heat, preferably to between 950° C. and 1100° C. for standard martensitic stainless steels. Thereafter, the automotive structural member is preferably cooled at a rate greater than 25° C. per minute to achieve a Rockwell C hardness of at least 39. The automotive structural member may undergo additional heat treating processes including high temperature or low temperature tempering processes which may incorporate electro-coating.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: January 13, 2009
    Assignee: KVA, Inc.
    Inventors: Edward J. McCrink, Danny Codd
  • Patent number: 7470336
    Abstract: A martensitic alloy in which the ASTM grain size number is at least 5, including (wt. %) up to about 0.5% C, at least about 5% Cr, at least about 0.5% Ni, up to about 15% Co, up to about 8% Cu, up to about 8% Mn, up to about 4% Si, up to about 6% (Mo+W), up to about 1.5% Ti, up to about 3% V, up to about 0.5% Al, and at least about 40% Fe.
    Type: Grant
    Filed: October 5, 2007
    Date of Patent: December 30, 2008
    Assignee: Advanced Steel Technology LLC
    Inventor: Robert F. Buck
  • Publication number: 20080274008
    Abstract: A corrosion-resistant steel excellent in toughness of a base metal and a weld portion said steel slab contains, in % by weight, C: 0.2% or less; Si: 0.01 to 2.0%; Mn: 0.1 to 4% or less; P: 0.03% or less; S: 0.01% or less; Cr: 3 to 11%; Al: 0.1 to 2%; and N: 0.02%, and has values of 1150 or above, and 600 or above respectively for Tp and Tc expressed by the equations below using concentrations of Cr, Al, C, Mn, Cu and Ni respectively given as % Cr, % Al, % C, % Mn, % Cu and % Ni. Tp=1601?(34% Cr+287% Al)+(500% C+33% Mn+60% Cu+107% Ni); and Tc=910+80% Al?(300% C+80% Mn+15% Cr+55% Ni).
    Type: Application
    Filed: May 12, 2004
    Publication date: November 6, 2008
    Inventors: Naoki Saitoh, Kenji Katoh
  • Patent number: 7429302
    Abstract: A structural hot-rolled or cold-rolled stainless steel sheet having improved intergranular corrosion resistance and toughness at the welding heat affected zone and further having low strength and high elongation. The composition of the steel sheet contains less than about 0.008 mass percent of C; about 1.0 mass percent or less of Si; about 1.5 mass percent or less of Mn; about 11 to about 15 mass percent of Cr; more than about 1.0 mass percent and about 2.5 mass percent or less of Ni; less than about 0.10 mass percent of Al; about 0.009 mass percent or less of N; about 0.04 mass percent or less of P; about 0.01 mass percent or less of S; and the balance being Fe and incidental impurities. These contents satisfy the expressions: (Cr)+1.2×(Ni)?15.0; (Ni)+0.5×(Mn)+30×(C)?3.0; (C)+(N)?0.015; and (Cr)?(Mn)?1.7×(Ni)?27×(C)?100×(N)?9.0.
    Type: Grant
    Filed: March 24, 2003
    Date of Patent: September 30, 2008
    Assignee: JFE Steel Corporation
    Inventors: Junichiro Hirasawa, Takumi Ujiro, Osamu Furukimi
  • Patent number: 7416619
    Abstract: The present invention relates to new kitchen utensils, in particular relates to an application of a material in kitchen utensils. The present invention solves the problems of long-term presence in the field. SUS436L is used for kitchen utensils. SUS436L chemical composition (wt %) comprises Cr 16-19, C?0.025, Si?1.00, Mn?1.00, N?0.02, Ni?0.60, Ti?0.75, Mo 0.75-1.50 and balance of Fe. The kitchen utensils have all excellence of present kitchen utensils, overcome its disadvantage and possess high property of heat conduction and magnetoconductivity. The kitchen utensils are used in induction cooker, possess the all and the one structure and have low cost.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: August 26, 2008
    Assignee: Xinhui Rixing Stainless Steel Product Company Limited
    Inventor: Iou Lei
  • Patent number: 7396421
    Abstract: A duplex stainless steel containing C, Si, Mn, P, S, Al, Ni, Cr, Mo, N (nitrogen, O (oxygen), Ca, Mg, Cu, B, and W, and the balance Fe and impurities, where a number of oxide-based inclusions, which have a total content of Ca and Mg of 20 to 40% by mass and also have a long diameter of not less than 7 ?m, is not more than a 10 per 1 mm2 of the cross section perpendicular to the working direction, or further, the number of oxide-based inclusions, which have a content of S of not less than 15% by mass and also have a long diameter of not less than 1 ?m, is not more than 10 per 0.1 mm2 of the cross section perpendicular to the working direction. Particularly, the contents of Cu, B and W are desirably 0.2 to 2%, 0.001 to 0.01%, and 0.1 to 4% by mass, respectively.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: July 8, 2008
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Tomohiko Omura, Satoshi Matsumoto
  • Publication number: 20080112839
    Abstract: A martensitic stainless steel for inexpensive seamless pipe having 655 MPa yield strength, high toughness and excellent corrosion resistance in high CO2 environments, and a method for manufacturing thereof is provided. The steel comprises C:0.005-0.05%, Si:0.1-0.5%, Mn: 0.1-2.0% P: ?0.005%, S: ?0.005%, Cr: 10.0-12.5%, Mo: 0.1-0.5%, Ni: 1.5-3.0%, N: ?0.02%, Al: 0.01-0.1%, by weight, while FI value defined by the formula [FI=Cr+Mo?Ni?30 (C+N)] being 5.00 to 8.49, and balance of substantially Fe. The method comprises the steps of reheating the cooled steel at temperatures from 780° C. to 960° C., quenching the reheated steel, and then tempering the quenched steel at temperatures from 550° C. to 650° C.
    Type: Application
    Filed: December 15, 2004
    Publication date: May 15, 2008
    Applicant: NKKTUBES
    Inventors: Shuji Hashizume, Yusuke Minami, Tatsuo Ono
  • Patent number: 7361235
    Abstract: A method of manufacturing an oxide dispersion strengthened ferritic steel excellent in high-temperature creep strength having a coarse grain structure. The method comprises mixing alloy powders and an Y2O3 powder, subjecting the mixed powder to mechanical alloying treatment, solidifying the alloyed powder by hot extrusion, and subjecting the extruded solidified material to final heat treatment involving heating to and holding at a temperature of not less than the Ac3 transformation point and slow cooling at a rate of not more than a ferrite-forming critical rate which comprises, 0.05-0.25% C, 8.0-12.0% Cr, 0.1-4.0% W, 0.1-1.0% Ti, 0.1-0.5% Y2O3 by weight, with the balance being Fe. In this method, by using a TiO2 powder as a Ti component to be mixed at the mechanical alloying treatment or by adding a Fe2O3 powder, the bonding of Ti with C is suppressed, and the C concentration in the matrix does not decrease.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: April 22, 2008
    Assignee: Japan Nuclear Cycle Development Institute
    Inventors: Satoshi Ohtsuka, Shigeharu Ukai, Takeji Kaito, Masayuki Fujiwara
  • Patent number: 7294212
    Abstract: Material for stainless steel sheets is heated to a temperature within a range of 850 to 1250° C. and cooled at a rate 1° C./s or faster, the material including 0.02% by mass or less of C, 1.0% by mass or less of Si, 2.0% by mass or less of Mn, 0.04% by mass or less of P, 0.01% by mass or less of S, 0.1% by mass or less of Al, 11% by mass or more but less than 17% by mass of Cr, 0.5% by mass or more but, less than 3.0% by mass of Ni, and 0.02% by mass or less of N, so as to satisfy specific relationships between the compositions.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: November 13, 2007
    Assignee: JFE Steel Corporation
    Inventors: Junichiro Hirasawa, Takumi Ujiro, Osamu Furukimi
  • Patent number: 7147726
    Abstract: The present invention concerns a mechanical method for generating nanostructures in order to obtain on a surface of a metal piece a nanostructured layer of defined thickness. A quantity of perfectly spherical balls (22) are disposed in a chamber that is closed for the size of the balls. At least one of the walls of the chamber supports or constitutes the piece to be treated (10). A vibrating motion is imparted to the chamber in a direction perpendicular to the plane of the circular motion of the chamber supporting or constituting the piece to be treated. The speed of the circular motion and the frequency and amplitude of the vibrating motion is determined based on the physical properties of the balls so as to communicate to the latter sufficient kinetic energy to create nanostructures on the material of the piece treated by impaction of the balloon surface of the piece.
    Type: Grant
    Filed: July 27, 2001
    Date of Patent: December 12, 2006
    Assignees: Universite de Technologie de Troyes, The Institute of Metal Research
    Inventors: Jian Lu, Ke Lu
  • Patent number: 6939419
    Abstract: The invention relates to plastic metal working, more specifically to methods for producing parts of the disk- or shell-type having conical, hemispherical, and also combined parts, such as disk-and-shaft ones. The invention is instrumental in producing large axially symmetric parts from hard-to-work multiphase alloys. The method consists in that the billet is heated in a temperature range above 0.4 m.p. but below the temperature at which a total content of precipitates or an allotropic modification of the matrix of a multiphase alloy is not below 7%. Then the preheated billet is rolled, while controlling its temperature and the tool load, as well as the rolling speed. Once rolled the billet is heat-treated at a temperature depending on the microstructure of the billet material resulting from rolling. Prerolling preparing of a specified microstructure of the billet material is also described.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: September 6, 2005
    Assignees: General Electric Company, Institute of Metals Superplascity Problems of Academy of Science
    Inventors: Farid Zainullaevich Utyashev, Oscar Akramovich Kaibyshev, Vener Anvarovich Valitov
  • Patent number: 6896747
    Abstract: Austenitic alloy for high-temperature strength with improved pourability and manufacturing, of which the composition comprises, in weight-%: 0.010%<carbon<0.04% 0%<nitrogen<0.01% silicon<2% 16%<nickel<19.9% manganese<8% 18.1%<chromium<21% 1.8%<titanium<3% molybdenum<3% copper<3% aluminum<1.5% boron<0.01% vanadium<2% sulfur<0.2% phosphorous<0.04% and possibly up to 0.5% of at least one element chosen from among yttrium, cerium, lanthanum and other rare earths, the remainder being iron and impurities resulting from manufacturing or deoxidizing, the said composition also satisfying the two following relationships: in relationship to the solidification mode: remainder a=eq. Nia?0.5×eq. Cra<3.60 where eq. Cra=Cr+0.7×Si+0.2×Mn+1.37×Mo+3×Ti+6×Al+4×V, and where eq. Nia=Ni+22×C+0.5×Cu, in relationship to the rate of residual ferrite: remainder b=eq. Nib?2×eq. Crb>?41 where eq. Crb=Cr+0.7×Si+1.37×Mo+3×Ti+6×Al+4×V, and where eq. Nib=Ni+22×C+0.5×Cu+0.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: May 24, 2005
    Assignee: Usinor
    Inventors: Jean-Michel Hauser, Christophe Bourgin
  • Patent number: 6893727
    Abstract: This invention relates to a stainless steel gasket having markedly improved strength and fatigue properties due to precipitation strengthening. Its composition comprises C: at most 0.03%, Si: at most 1.0%, Mn: at most 2%, Cr: 16.0%-18.0%, Ni: 6.0%-8.0%, N: at most 0.25%, if necessary Nb: at most 0.30%, and a remainder of Fe and unavoidable impurities. After cold rolling, final annealing is carried out, and after a structure is formed of recrystallized grains with an average grain diameter of at most 5 ?m having an area ratio of 50-100% and an unrecrystallized portion having an area ratio of 0-50%, a metal gasket is formed by steps including temper rolling with a reduction of at least 30% to make the area ratio of a strain induced martensite phase at least 40%, and forming and heat treatment at 200-350° C.
    Type: Grant
    Filed: October 24, 2003
    Date of Patent: May 17, 2005
    Assignees: Sumitomo Metal Industries, Ltd., Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kazuhiko Adachi, Seishi Ishiyama, Kenichi Goshokubo, Takashi Katsurai
  • Patent number: 6855213
    Abstract: A ferritic non-ridging stainless steel and process therefor. A chromium alloyed steel melt containing sufficient titanium and nitrogen but a controlled amount of aluminum is cast into an ingot or continuously cast into a strip or a slab having an as-cast fine equiaxed grain structure substantially free of columnar grains. The as-cast steel contains 0.08% C, at least about 8% Cr, up to 1.50% Mn, <0.020% Al, ?0.05% N, ?1.5% Si, <2.0% Ni, Ti?0.10%, the ratio of (Ti×N)/Al?0.14, all percentages by weight, the balance Fe and residual elements. Preferably, the titanium is controlled so that (Ti/48)/[(C/12)+(N/14)]>1.5. A hot processed sheet may be formed from a continuously cast slab without grinding the surfaces of the slab. The hot processed sheet may be descaled, cold reduced to a final thickness and recrystallization annealed. Annealing the hot processed sheet prior to cold reduction is not required to obtain an annealed sheet essentially free of ridging and having high formability.
    Type: Grant
    Filed: September 15, 1998
    Date of Patent: February 15, 2005
    Assignee: Armco Inc.
    Inventors: Eizo Yoshitake, Alan R. McKague
  • Publication number: 20040265162
    Abstract: Ferritic stainless steel, comprising the following Chemical elements expressed in percentage by weight: —Cr 14.0-20.0 —Al 0.50-1.50 —Zr 0.10-0.50 —Si 0.30-1.50 —Ti 0.10-0.35 —Nb 0.25-0.55 —C<0.035 —N<0.035 provided that the content of Ti, Nb, C and N satisfy the following relation: %Ti+%Nb/1.94>9 (%C+%N) and substantially iron q. s. to 100. This steel may also comprise Yttrium and/or rare earth elements in a percentage by weight comprised in the range 0.10-0.30. The invention also encompasses products manufacturable with the steel of the invention, in particular vehicle exhaust manifold systems. Figure (I) shows a cyclic oxidation test carried out at 1000° C. on samples having the composition of an embodiment of the steel according to the invention.
    Type: Application
    Filed: August 20, 2004
    Publication date: December 30, 2004
    Inventor: Gianni Songini
  • Publication number: 20040226634
    Abstract: Material for stainless steel sheets is heated to a temperature within a range of 850 to 1250° C. and cooled at a rate 1° C./s or faster, the material including 0.02% by mass or less of C, 1.0% by mass or less of Si, 2.0% by mass or less of Mn, 0.04% by mass or less of P, 0.01% by mass or less of S, 0. 1% by mass or less of Al, 11% by mass or more but less than 17% by mass of Cr, 0.5% by mass or more but, less than 3.0% by mass of Ni, and 0.02% by mass or less of N, so as to satisfy specific relationships between the compositions.
    Type: Application
    Filed: April 30, 2004
    Publication date: November 18, 2004
    Applicant: JFE STEEL CORPORATION
    Inventors: Junichiro Hirasawa, Takumi Ujiro, Osamu Furukimi
  • Publication number: 20040206427
    Abstract: An austenitic stainless steel which comprises, on the percent by mass basis, C: 0.03-0.12%, Si: 0.2 -2%, Mn: 0.1-3%, P: 0.03% or less, S: 0.01% or less, Ni: more than 18% and less than 25%, Cr: more than 22% and less than 30%, Co: 0.04-0.8%, Ti: 0.002% or more and less than 0.01%, Nb: 0.1-1%, V:0.01 -1%, B: more than 0.0005% and 0.2% or less, sol. Al: 0.0005% or more and less than 0.03%, N: 0.1-0.35% and 0 (Oxygen): 0.001-0.008%, with the balance being Fe and impurities can be utilized as materials such as steel tubes used as a superheater tube, reheater tube for a boiler and a furnace tube for the chemical industry, and a steel plate, a steel bar and a steel forging and the like, which are used as a heat resistant, pressure-tight member, whereby extremely large effects on the promotion of increasing high temperature and high pressure steam in a boiler for an electric power-generation can be obtained.
    Type: Application
    Filed: January 21, 2004
    Publication date: October 21, 2004
    Inventors: Atsuro Iseda, Hiroyuki Semba
  • Publication number: 20040154706
    Abstract: An iron based, fine-grained, martensitic stainless steel essentially free of delta ferrite has a nominal composition of (wt. %): 0.05<C<0.15; 7.5<Cr<15; 2<Ni<5; Co<4; Cu<1.2; Mn<5; Si<1; (Mo+W)<4; 0.01<Ti<0.75; 0.135<(1.17Ti+0.6Zr+0.31Ta+0.31Hf)<1; V<2; Nb<1; N<0.02; Al<0.2; Al and Si both present such that (Al+Si)>0.01; B<0.1; P<0.1; S<0.03; and the balance essentially iron and impurities. This steel is different from other martensitic stainless steels because thermal mechanical treatment is used to refine the grains and precipitate a relatively uniform dispersion of fine, coarsening-resistant, MX-type particles. The steel combines high strength and impact toughness with good corrosion resistance.
    Type: Application
    Filed: May 8, 2003
    Publication date: August 12, 2004
    Inventor: Robert F. Buck
  • Publication number: 20040154707
    Abstract: An iron based, fine-grained, alloy.
    Type: Application
    Filed: November 12, 2003
    Publication date: August 12, 2004
    Inventor: Robert F. Buck
  • Publication number: 20040140023
    Abstract: A ferritic stainless steel sheet, which is press-formed to a product shape without such dimensional defects as spring-back or torsion, has an alloying composition consisting of C up to 0.10%, Si up to 1.0%, Mn up to 1.0%, P up to 0.050%, S up to 0.020%, Ni up to 2.0%, 8.0-22.0% of Cr, N up to 0.05%, optionally one or more of Al up to 0.10%, Mo up to 1.0%, Cu up to 1.0%, 0.010-0.50% of Ti, 0.010-0.50% of Nb, 0.010-0.30% of V, 0.010-0.30% of Zr and 0.0010-0.0100% of B, and the balance being essentially Fe with the provision that a value-FM defined by the formula (1) is adjusted to 0 or less. Its mechanical properties are controlled to a plane anisotropic degree (rmax−rmin) of Lankford value (r) ≦0.80 and an anisotropic degree (&sgr;max−&sgr;min) of 0.2%-yield strength ≦20 N/mm2. The stainless steel sheet is manufactured by hot-rolling a stainless steel having the specified composition and then batch-annealing the hot-rolled steel sheet 1-24 hours at 700-800° C.
    Type: Application
    Filed: November 6, 2003
    Publication date: July 22, 2004
    Inventors: Kouki Tomimura, Hiroshi Fujimoto, Kenichi Morimoto, Yasutoshi Kunitake, Naoto Hiramatsu
  • Publication number: 20040074574
    Abstract: A high-Cr containing ferrite heat resistant steel having not only an excellent long-term creep strength at a high temperature exceeding 650° C., but also an improved oxidation resistance, which is based on ferritic phase and contains 13% by weight or more of chromium, and containing precipitates of intermetallic compounds.
    Type: Application
    Filed: October 10, 2003
    Publication date: April 22, 2004
    Inventor: Kazuhiro Kimura
  • Publication number: 20040060621
    Abstract: The invention provides a ferritic heat-resistant steel having excellent high-temperature oxidation resistance, especially excellent steam oxidation-resistant characteristics. In high-Cr ferritic heat-resistant steel, ultra-fine oxide particles having a size of not larger than 1 &mgr;m are formed just below the oxide films and formed on the steel base, whereby the adhesiveness between the films and the base is enhanced. The ferritic heat-resistant steel contains Cr in an amount of from 8.0 to 13.0% by weight, and at least one of Rh and Ir in a total amount of from 0.3 to 5.0% by weight.
    Type: Application
    Filed: September 30, 2003
    Publication date: April 1, 2004
    Inventors: Nobuyuki Fujitsuna, Fujio Abe, Takehiko Itagaki, Masaki Igarashi, Seiichi Muneki, Kazuhiro Kimura, Hideaki Kushima
  • Publication number: 20040003876
    Abstract: A structural Fe—Cr steel sheet and a manufacturing method thereof are provided, the steel sheet having an as-hot rolled tensile strength of about 400 to about 450 MPa and generating no embrittlement in welded portions even when rapid heating and cooling is performed by electric resistance welding. In addition, structural shaped steel is also provided which is formed from the steel sheet described above by using electric resistance welding.
    Type: Application
    Filed: June 25, 2003
    Publication date: January 8, 2004
    Applicant: JFE Steel Corporation, a corporation of Japan
    Inventors: Hiroki Ota, Takumi Ujiro, Osamu Furukimi, Noriyuki Matsuo, Hiroyuki Nakashima, Masato Shigemi, Toshihiro Kasamo
  • Publication number: 20030188813
    Abstract: A structural hot-rolled or cold-rolled stainless steel sheet having improved intergranular corrosion resistance and toughness at the welding heat affected zone and further having low strength and high elongation. The composition of the steel sheet contains less than about 0.008 mass percent of C; about 1.0 mass percent or less of Si; about 1.5 mass percent or less of Mn; about 11 to about 15 mass percent of Cr; more than about 1.0 mass percent and about 2.5 mass percent or less of Ni; less than about 0.10 mass percent of Al; about 0.009 mass percent or less of N; about 0.04 mass percent or less of P; about 0.01 mass percent or less of S; and the balance being Fe and incidental impurities. These contents satisfy the expressions: (Cr)+1.2×(Ni)≧15.0; (Ni)+0.5×(Mn)+30×(C)≦3.0; (C)+(N)≦0.015; and (Cr)−(Mn)−1.7×(Ni)−27×(C)−100×(N)≧9.0.
    Type: Application
    Filed: March 24, 2003
    Publication date: October 9, 2003
    Applicant: KAWASAKI STEEL CORPORATION
    Inventors: Junichiro Hirasawa, Takumi Ujiro, Osamu Furukimi
  • Publication number: 20030138342
    Abstract: A martensitic stainless steel sheet having superior corrosion resistance, toughness at the weld zones, and workability. The composition of the steel sheet is, on a mass basis: less than about 0.02% of carbon; about 1.0% or less of silicon; less than about 1.5% of manganese; about 0.04% or less of phosphorus; about 0.01% or less of sulfur; about 0.1% or less of aluminum; about 1.5% or more and less than about 4.0% of nickel; about 11% or more and less than about 15% of chromium; about 0.5% or more and less than about 2.0% of molybdenum; and less than about 0.02% of nitrogen, the balance being iron and unavoidable impurities, wherein 15.0%≦[Cr]+1.5×[Mo]+1.2×[Ni]≦20.0%; [C]+[N]<0.030%; [Ni]+0.5×([Mn]+[Mo])+30×[C]>3.0%; and 8.
    Type: Application
    Filed: December 23, 2002
    Publication date: July 24, 2003
    Applicant: Kawasaki Steel Corporation
    Inventors: Junichiro Hirasawa, Takumi Ujiro, Osamu Furukimi
  • Publication number: 20030127163
    Abstract: The invention provides a ferritic heat-resistant steel having excellent high-temperature oxidation resistance, especially excellent steam oxidation-resistant characteristics. In high-Cr ferritic heat-resistant steel, ultra-fine oxide particles having a size of not larger than 1 &mgr;m are formed just below the oxide films and formed on the steel base, whereby the adhesiveness between the films and the base is enhanced. The ferritic heat-resistant steel contains Cr in an amount of from 8.0 to 13.0% by weight, and at least one of Rh and Ir in a total amount of from 0.3 to 5.0% by weight.
    Type: Application
    Filed: July 22, 2002
    Publication date: July 10, 2003
    Inventors: Nobuyuki Fujitsuna, Fujio Abe, Takehiko Itagaki, Masaaki Igarashi, Seiichi Muneki, Kazuhiro Kimura, Hideaki Kushima
  • Patent number: 6478900
    Abstract: An improved method of forging a precipitation hardening type stainless steel. The method comprises the steps of soaking the precipitation hardening type stainless steel at a temperature of austenitizing range, cooling the steel to a temperature in the range of 200-700° C., preferably 400-600° C., and subjecting the steel to forging at the temperature in this range. Conventional lubricants and die cooling oils can be used without being deteriorated due to high temperature. It is preferable to forcibly cool the soaked steel to adjust the temperature of the steel at which it is forged. The forged steel is then age hardened to exhibit inherent hardness.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: November 12, 2002
    Assignee: Diado Tokushuko Kabushiki Kaisha
    Inventors: Sachihiro Isogawa, Masamichi Kawano, Katsuyoshi Sakoda
  • Publication number: 20020162614
    Abstract: Maraging steel with improved machinability, good weldability, and high corrosion resistance, a process for the heat treatment of such a steel, as well as its use. According to the invention this steel contains (in % by weight) 0.02-0.075% carbon; 0.1-0.6% silicon; 0.5-0.9% manganese; 0.08-0.25% sulfur; maximum 0.04%; phosphorus; 12.4-15.2% chromium; 0.05-1.0% molybdenum; 0.2-1.8% nickel; maximum 0.15% vanadium; 0.1-0.45% copper; maximum 0.03% aluminum; 0.02-0.08% nitrogen; as well as optionally one or more additional alloying elements up to maximum 2.0%, residual iron, and impurities caused in manufacturing, and a ferrite percentage in the structure of less than 28% by volume.
    Type: Application
    Filed: February 13, 2002
    Publication date: November 7, 2002
    Applicant: BOHLER EDELSTAHL GmbH
    Inventors: Klaus Sammt, Johann Sammer, Gerhard Lichtenegger
  • Publication number: 20020112795
    Abstract: A stainless steel hydraulic component and method for making same hard turns a pre-heat treated stainless steel material, preferably a 400 series stainless steel material, provided in bar stock form in a single machining loading. Stainless steel hydraulic valve components made therefrom have shown improved leakage rate performance with the performance being fairly constant over a period of time for providing a longer functional life for the hydraulic valve component.
    Type: Application
    Filed: December 13, 2000
    Publication date: August 22, 2002
    Applicant: Eaton Corporation
    Inventors: Daniel P. Rohde, John N. Tackes
  • Patent number: 6423160
    Abstract: A stainless steel plate for a shadow mask, comprising 9 to 20 weight % of chromium (Cr), 0.15 weight % or less of carbon (C), 0 to 1.0 weight % of manganese (Mn), 0 to 0.2 weight % of titanium (Ti), 0 to 1.0 weight % of silica (Si), and 0 to 1.0 weight % of aluminum (Al); wherein the rest includes ferrite (Fe) and inevitable impurities, and in the inevitable impurities, the content of phosphor (P) is 0.05 weight % or less and the content of sulfur (S) is 0.03 weight % or less. Furthermore, the metal plate for a shadow mask after cold rolling or shape correction is performed is subjected to annealing treatment at the end-point temperature of the plate of 550 to 650° C. This steel plate has a coefficient of thermal expansion smaller than that of low carbon steel and is less expansive than invar alloy. Further, the steel plate has high strength that is acceptable for the shadow mask that is used under conditions where plastic deformation is small at high temperature and high tension is applied.
    Type: Grant
    Filed: January 4, 2001
    Date of Patent: July 23, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nozomu Arimoto, Hayato Kita, Masahiro Aoki, Shinji Tsuge, Kazuhiko Adachi
  • Patent number: 6419770
    Abstract: The high carbon stainless steel containing more than 0.5 mass % carbon and more than 8 mass % chromium, or the tool steel containing more than 0.5 mass % carbon and more than 0.5 mass % at least one of carbide producing metal elements including chromium, molybdenum, tungsten, vanadium, niobium and titanium is processed by cold-warm working such as forging at a temperature of less than 800 ° C. to make more than 10% plastic deformation to an extent that cracks and voids are formed in the crystallized first stage carbide and, further, processed by a Hot Isostatic Pressing treatment so that the cracks and voids may be cured.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: July 16, 2002
    Assignee: DENSO Corporation
    Inventors: Shu Miyashita, Masami Tanaka, Saburo Sugiura, Yoshitaka Nishizawa
  • Publication number: 20020088513
    Abstract: A manufacturing mold base for plastic injection molds is formed from a martensitic stainless steel alloy comprising: about 0.03%-0.06% by weight C, about 1.0%-1.6% by weight Mn, about 0.01%-0.03% by weight P, about 0.06%-0.3% by weight S, about 0.25%-1.0% by weight Si, about 12.0%-14.0% by weight Cr, about 0.5%-1.3% by weight Cu, about 0.01%-0.1% by weight V, about 0.02%-0.08% by weight N, with the balance being Fe with trace amounts of ordinarily present elements.
    Type: Application
    Filed: January 18, 2002
    Publication date: July 11, 2002
    Inventors: Eric D. Henn, Robert J. Friedrich, Michael A. Guscott
  • Publication number: 20020084008
    Abstract: A surface treatment process for enhancing the resistance to intergranular corrosion and intergranular cracking of components fabricated from austenitic Ni—Fe—Cr based alloys comprising the application of surface deformation to the component, to a depth in the range of 0.01 mm to 0.5 mm, for example by high intensity shot peening below the recrystallization temperature, followed by recrystallization heat treatment, preferably at solutionizing temperatures. The surface deformation and annealing process can be repeated to further optimize the microstructure of the near-surface region. Following the final heat treatment, the process optionally comprises the application of further surface deformation (work) of reduced intensity, yielding a worked depth of between 0.005 mm to 0.01 mm, to impart residual compression in the near surface region to further enhance cracking resistance.
    Type: Application
    Filed: November 27, 2001
    Publication date: July 4, 2002
    Inventors: David L. Limoges, Gino Palumbo, Peter K. Lin
  • Patent number: 6391253
    Abstract: The present invention provides a stainless steel being excellent in workability, corrosion resistance and antibacterial property. To be more specific, a stainless steel containing 10 wt % or more of Cr is rendered to contain 0.0001-1 wt % of Ag, or further one or more members selected from Sn: 0.0002-0.02 wt %, Zn: 0.0002-0.02 wt %, Pt: 0.0002-0.01 wt %, and, in addition, is rendered to dispersedly contain a total of 0.001 % or more in an area percentage of one or more members of a silver particle, a silver oxide and a silver sulphide each having a mean grain diameter of 500 &mgr;m or less. To disperse the silver particle, silver oxide and silver sulphide uniformly, the casting rate of continuous casting is preferably controlled to range from 0.8 to 1.6 m/min.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: May 21, 2002
    Assignee: Kawasaki Steel Corporation
    Inventors: Misako Tochihara, Takeshi Yokoto, Susumu Satoh, Sadao Hasuno
  • Patent number: 6329081
    Abstract: There is provided a stainless steel sheet material, used for a semiconductor manufacturing device, to which it difficult for fine dust to be attached and from the surface of which the attaching dust can be easily washed away. Also, there is provided a method of manufacturing the stainless steel sheet material. A stainless steel sheet material characterized in that: the number of pinholes, the area of each pinhole exceeding 0.25 mm2, in the area of 10 cm2 on the surface of a skinpass-rolled stainless steel sheet material is not more than 10; and the average surface roughness Ra on the center line in the direction perpendicular to the rolling direction is not more than 0.15 &mgr;m. A method of manufacturing a stainless steel sheet material comprising the steps of: annealing a stainless steel cold-rolled sheet in a heat-treatment furnace having no support rollers in a temperature region exceeding 600° C.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: December 11, 2001
    Assignee: Nippon Steel Corporation
    Inventors: Fumio Fudanoki, Toshihiko Sugimoto, Satoshi Akamatsu, Masanori Hashimoto
  • Patent number: 6306230
    Abstract: A method for producing hardened parts of steel from an air-hardening steel comprising the steps of heating the steel is heated to a temperature above 1,100° C., hot-working the steel parts until they reach the A1 emperature, cooling the steel parts in air to about 280° C. under simultaneous thermo-mechanical sizing treatment, then cooling the steel parts in air to room temperature, stress relief treating the steel parts at 150-250° C., and hard-machining the steel parts.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: October 23, 2001
    Assignee: SKF GmbH
    Inventor: Frank Hengerer
  • Publication number: 20010023725
    Abstract: The proposed brake disk consists of steel of a composition of 0.1 to 0.4% of carbon, up to 1.0% of silicon, up to 2.0% of manganese, up to 0.02% of sulfur, 11 to 16% of chromium, up to 1.0% of nickel and 0.5 to 1.5% of molybdenum, the remainder being iron and production-related impurities.
    Type: Application
    Filed: February 28, 2001
    Publication date: September 27, 2001
    Inventor: Walter Grimm
  • Patent number: 6217679
    Abstract: The invention provides hot-rolled steel strips which, after having been acid-pickled, can be directly used. The strips have no Cr-decreasing layer and no shot blasted marks on their surface and have good corrosion resistance. The invention also provides a technique of efficiently producing the hot-rolled steel strips. A steel slab having a Cr content of from 6.0 to 25.0 wt. % is hot-rolled, then coiled at a temperature not higher than 700° C., then optionally quenched in water immediately after the coiling, then annealing in a reducing atmosphere, and thereafter acid-pickled in a solution of nitric acid/hydrochloric acid.
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: April 17, 2001
    Assignee: Kawasaki Steel Corporation
    Inventors: Masaaki Kohno, Kunio Fukuda, Kazuhide Ishii, Susumu Satoh, Hiroshi Yaginuma, Takumi Ujiro
  • Patent number: 6203632
    Abstract: The invention relates to iron-chromium aluminum metal foil which is resistant to high-temperature oxidation. Said metal foil is produced by hot-dip aluminizing an iron-chromium support band with an aluminum-silicon alloy. The foil has the following composition in weight percent: 18-25% Cr. 4-10% Al, 0.03-0.08% Y, max. 0.01% Ti, 0.01-0.05% Zr, 0.01-0.05% Hf, 0.5-1.5% Si. It also contains residual iron and impurities resulting from the method of production. The total aluminum content of the coated metal foil is at least 7% near the surface and not less than 3% further inside.
    Type: Grant
    Filed: July 1, 1999
    Date of Patent: March 20, 2001
    Assignee: Krupp VDM GmbH
    Inventors: Ulrich Heubner, Angelika Kolb-Telieps, Ralf Hojda
  • Patent number: 6193469
    Abstract: A high toughness heat-resistant steel, a turbine rotor formed of this steel and a method of producing the turbine rotor are described. The heat-resistant steel has a composition consisting essentially of: 0.05 to 0.30 wt % C, 0 to 0.20 wt % Si, 0 to 1.0 wt % Mn, 8.0 to 14.0 wt % Cr, 0.5 to 3.0 wt % Mo, 0.10 to 0.50 wt % V, 2.0 to 5.0 wt % Ni, 0.01 to 0.50 wt % Nb, 0.01 to 0.08 wt % N, 0.001 to 0.020 wt % B, balance Fe and unavoidable impurities. The steel has excellent characteristics in not only tensile strength and toughness at a relatively low temperature condition of a steam turbine such as high/low pressure combined type one but also creep rupture strength at a high temperature condition of this turbine.
    Type: Grant
    Filed: March 24, 1998
    Date of Patent: February 27, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoichi Tsuda, Ryuichi Ishii, Masayuki Yamada