Nine Percent Or More Chromium Containing Patents (Class 148/325)
  • Patent number: 6780258
    Abstract: A new austenitic stainless steel containing approximately 0.1-1.0 mass % of Si and not more than approximately 0.003 mass % of Al. Nonmetallic inclusions dispersed in a steel matrix are converted to MnO—SiO2—Al2O3 containing not less than approximately 15 mass % of SiO2 and not more than approximately 40 mass % of Al2O3. During steel making, molten steel is covered with basic slag and heavily deoxidized with a Si alloy whose Al content is controlled to not more than approximately 1.0 mass % in a vacuum or non-oxidizing atmosphere. The austenitic stainless steel sheet can be formed to an objective shape without the occurrence of cracking due to its decrease in susceptibility to cracking and its good formability.
    Type: Grant
    Filed: January 8, 2002
    Date of Patent: August 24, 2004
    Assignee: Nisshin Steel Co., Ltd.
    Inventors: Junichi Katsuki, Teruyoshi Iida, Takashi Yamauchi, Satoshi Suzuki, Naoto Hiramatsu
  • Patent number: 6780257
    Abstract: A base plate of a stainless-steel body material formed by pressing is polished and cleared of burrs by means of an abrasive material that consists mainly of Fe2O3 in a polishing process. The polished base plate is heated to a heat treatment temperature for solid solution in a reducing atmosphere in a heat treatment process. In this heat treatment process, an oxide in the constituents of minute fragments of the abrasive material in the surface of the body material of the base plate is reduced to leave iron, which is dispersed into the body material.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: August 24, 2004
    Assignees: IBM Japan Ltd., NHK Spring Co., Ltd.
    Inventors: Tsuyoshi Nagata, Hiroyasu Tsuchida, Yoshio Uematsu, Kiyoshi Satoh, Kosuke Tamaru
  • Publication number: 20040159380
    Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.
    Type: Application
    Filed: February 17, 2004
    Publication date: August 19, 2004
    Applicant: JFE Steel Corporation
    Inventors: Yoshihiro Yazawa, Osamu Furukimi, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Yukihiro Baba
  • Patent number: 6776956
    Abstract: Provided is a steel for separators of solid-oxide type fuel cells, which forms oxide films having good electrical conductivity at 700 to 950° C. or so, has good oxidation resistance and, in particular, resistance to exfoliation even in the case of long hours of use, is excellent in impact properties at room temperature, shows a small difference in thermal expansion from the electrolyte, and is inexpensive. This steel for separators of solid-oxide fuel cells includes, by mass %, not more than 0.2% C, not more than 1.0% Si, not more than 1.0% Mn, not more than 2% Ni, 15 to 30% Cr, not more than 1% Al, one or more elements selected from the group of not more than 0.5% Y, not more than 0.2% REM and not more than 1% Zr, and the balance of Fe and unavoidable impurities. In this steel, amounts of S, O, N and B in the unavoidable impurities are restricted to not more than 0.015%, not more than 0.010%, not more than 0.050% and not more than 0.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: August 17, 2004
    Assignee: Hitachi Metals Ltd.
    Inventors: Toshihiro Uehara, Akihiro Toji, Takehiro Ohno
  • Publication number: 20040154708
    Abstract: The present invention provides a ferritic stainless steel casting and a sheet thereof excellent in deep drawability, punch stretchability and ridging resistance and a method for producing the casting and the sheet. In the present invention, a chemical composition is controlled so that the amounts of C, N, Si, Mn, P and Ti may be reduced to the utmost for securing high workability and, on the basis of the chemical composition, the roping and ridging of a steel sheet product is reduced by adding Mg, thus dispersing Mg containing oxides that accelerate the formation of nuclei for solidification and, resultantly, suppressing the development of coarse columnar crystals in a casting.
    Type: Application
    Filed: November 25, 2003
    Publication date: August 12, 2004
    Inventors: Akihiko Takahashi, Junichi Hamada, Ken Kimura, Takashi Morohoshi, Yoshihito Yamada, Toyohiko Kakihara, Satoshi Hashimoto
  • 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: 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
  • Patent number: 6770243
    Abstract: A chromium steel alloy having 0.4 to 0.75% of carbon, 0.4 to 1.6% of manganese, 12 to 19% of chromium, up to 0.2% of nickel, up to 0.7% of silicon, 0.5 to 1.5% of molybdenum, up to 1.5% of tungsten, 0.05 to 0.3% of vanadium and (% Ti/% Nb), 0.02 to 0.15% of sulfur, up to 0.1% of nitrogen and up to 0.008% of boron, remainder iron including smelting-related impurities. This steel alloy is distinguished by good processability, resistance to corrosion, resistance to abrasion, a high resistance to heat up to 300° C. and above, and a high rigidity.
    Type: Grant
    Filed: July 17, 2002
    Date of Patent: August 3, 2004
    Assignee: Stahlwerk Ergste Westig GmbH
    Inventors: Gisbert Kloss-Ulitzka, Gunter Schnabel, Oskar Pacher
  • Patent number: 6767416
    Abstract: A corrosion resistant, high strength austenitic stainless steel consisting of 1.0% or less of Si, 2.0% or less of Mn, 0.5% or less of O, 7 to 30% of Ni, 14 to 26% of Cr, 0.3% or less of combination of C and N, at least one element selected from the group consisting of 1.0% or less of Ti, 2.0% or less of Zr and 2.0% or less of Nb, and the balance consisting of Fe and unavoidable impurities, the percentage being given in weight basis; said steel containing carbonitride with a grain size of several to 100 nm dispersed therein; said steel having an average crystal grain size of 1 &mgr;m or less; and said steel containing 90% by volume or more of austenite phase; is excellent in strength and corrosion resistance.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: July 27, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Ryo Ishibashi, Yasuhisa Aono
  • 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
  • Patent number: 6763593
    Abstract: Provided is a razor blade material which has excellent high hardness, high strength and high corrosion resistance. The material is made of an Fe-base alloy containing, by mass %, not less than 0.5% carbon, 9.0 to 14.0% Cr and from more than zero to 8.0% Mo, wherein precipitates, which can be observed at an optional cross section of the razor blade material, have a diameter of less than 0.1 m. The alloy has preferably a chemical composition of 0.5 to 5.0% carbon, 9.0 to 14.0% Cr and 0.5 to 8.0% Mo, 0.5 to 8.0% of B+Si, and the balance of Fe and unavoidable impurities. Preferably, the alloy has a metal structure, not less than 30 volume % of which is amorphous. The material has a thickness of 30 to 100 &mgr;m. The razor blade is preferably coated with polytetrafluoroethylene (PTFE).
    Type: Grant
    Filed: January 24, 2002
    Date of Patent: July 20, 2004
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hideshi Nakatsu, Yasushi Tamura
  • Patent number: 6764555
    Abstract: A high-strength austenitic stainless steel strip exhibiting excellent flatness with Vickers hardness of 400 or more has the composition comprising: C up to 0.20 mass %, Si up to 4.0 mass %, Mn up to 5.0 mass %, 4.0-12.0 mass % Ni, 12.0-20.0 mass % Cr, Mo up to 5.0 mass %, N up to 0.15 mass % and the balance being Fe except inevitable impurities having a value Md(N) in a range of 0-125 defined by the formula Md(N)=580-520C-2Si-16Mn-16Cr-23Ni-26Cu-300N-10Mo. The material has a dual-phase structure of austenite and martensite involving a reverse-transformed austenite at a ratio of 3 vol. % or more. The material is manufactured by solution-heating a steel strip having the above composition, cold-rolling the steel strip to generate a deformation-induced martensite, and then re-heating at 500-700° C. to induce a phase reversion from martensite to at least 3 vol. % austenite. The reversion effectively flattens the steel strip.
    Type: Grant
    Filed: December 3, 2001
    Date of Patent: July 20, 2004
    Assignee: Nisshin Steel Co., Ltd.
    Inventors: Naoto Hiramatsu, Kouki Tomimura, Hiroshi Fujimoto, Kenichi Morimoto
  • Patent number: 6761777
    Abstract: The present invention is directed to a corrosion and erosion resistant High Chromium, Nitrogen bearing alloy, comprising the following composition in wt. %: 28-48 chromium, 0.01-0.7 nitrogen, 0.5-30 manganese, 0.01-5 boron, 0.3-2.5 carbon, up to 0.01-25 cobalt plus nickel, up to 0.01-5 silicon, up to 0.01-8 copper, up to 0.01-6 molybdenum, up to 2% of each one selected from group consisting of zirconium, vanadium, cerium, titanium, tungsten, niobium, aluminum, calcium, and rare earth elements with the balance being essentially iron and other trace elements or inevitable impurities. The alloy has a microstructure comprising hypoeutectic, eutectic, chromium carbides, boride and nitrides in the austenitic matrix, saturated with nitrogen with virtually no secondary carbides and nitrides.
    Type: Grant
    Filed: January 9, 2002
    Date of Patent: July 13, 2004
    Inventor: Roman Radon
  • Patent number: 6761751
    Abstract: A method of producing an FeCrAl material by gas atomization, and a high temperature material produced by the method. In addition to containing iron (Fe), chromium (Cr), and aluminium (Al) the material also contains minor fractions of one or more of the materials molybdenum (Mo), hafnium (Hf), zirconium (Zr), yttrium (Y), nitrogen (N), carbon (C) and oxygen (O). The smelt to be atomized contains 0.05-0.50 percent by weight tantalum (Ta) and less than 0.10 percent by weight titanium (Ti). Nitrogen gas (N2) is used as an atomizing gas, to which an amount of oxygen gas (O2) is added, the amount of oxygen gas being such as to cause the atomized powder to contain 0.02-0.10 percent by weight oxygen (O) and 0.01-0.06 percent by weight nitrogen (N).
    Type: Grant
    Filed: October 16, 2002
    Date of Patent: July 13, 2004
    Assignee: Sandvik AB
    Inventors: Roger Berglund, Bo Jönsson, Jonas Magnusson
  • Publication number: 20040129347
    Abstract: Alloy compositions suitable for fabricating medical devices, such as stents, are disclosed. In certain embodiments, the compositions have small amounts of nickel, e.g., the compositions can be substantially free of nickel.
    Type: Application
    Filed: January 8, 2003
    Publication date: July 8, 2004
    Inventor: Charles Horace Craig
  • Patent number: 6755919
    Abstract: A stainless steel tube having excellent formability for secondary operation comprises: a chemical composition including not more than 0.20 mass % of C; not more than 1.5 mass % of Si; not more than 2.0 mass % of Mn; 10-18 mass % of Cr; not more than 0.03 mass % of N; or further at least one type of element selected from the group of: not more than 0.6 mass % of Cu; not more than 0.6 mass % of Ni; not more than 2.5 mass % of Mo; not more than 1.0 mass % of Nb; not more than 1.0 mass % of Ti; and not more than 1.0 mass % of V; Fe as the remainder and the inevitable impurities; and a structure constituted of ferrite or ferrite and martensite, wherein the TE value defined by the following formula exceeds 25,000 Mpa·%, TE=TS×(El+21.9) TS represents the tensile strength in the tube axial direction, and El represents the elongation in such direction.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: June 29, 2004
    Assignee: JFE Steel Corporation
    Inventors: Takaaki Toyooka, Akira Yorifuji, Makoto Kitazawa, Yoshikazu Kawabata, Motoaki Itadani, Masatoshi Aratani, Takatoshi Okabe
  • Patent number: 6749697
    Abstract: The present invention relates to a duplex stainless steel alloy with austenite-ferrite structure, which in hot extruded and annealed finish shows high strength, good corrosion resistance, as well as good weldability which is characterized in that the alloy contains in weight-% max 0.05% C, 0-2.0% Si 0-3.0% Mn, 25-35% Cr, 4-10% Ni, 2-6% Mo, 0.3-0.6% N, as well as Fe and normally occurring impurities and additions, whereby the content of ferrite is 30-70%.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: June 15, 2004
    Assignee: Sandvik AB
    Inventors: Örjan Bergström, Pasi Kangas, Mattias Klockars, Guocai Chai
  • Patent number: 6740174
    Abstract: The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10×(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si ≦1.2−0.4 Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: May 25, 2004
    Assignee: JFE Steel Corporation
    Inventors: Atsushi Miyazaki, Junichiro Hirasawa, Mineo Muraki, Yoshihiro Yazawa, Osamu Furukimi
  • Publication number: 20040094240
    Abstract: A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.
    Type: Application
    Filed: November 17, 2003
    Publication date: May 20, 2004
    Applicant: JFE Steel Corporation, a corporation of Japan
    Inventors: Yoshihiro Yazawa, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Atsushi Miyazaki, Yasushi Katoh
  • Patent number: 6733601
    Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5 % Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and. Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.
    Type: Grant
    Filed: January 14, 2002
    Date of Patent: May 11, 2004
    Assignee: JFE Steel Corporation
    Inventors: Yoshihiro Yazawa, Osamu Furukimi, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Yukihiro Baba
  • 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
  • Patent number: 6723182
    Abstract: A cobalt-free martensitic steel exhibiting good response to hardening and resistance to softening at high temperatures, the steel containing sub-micron and nano-structural precipitates and intermetallic compounds of silicon, nickel, aluminum, copper and manganese.
    Type: Grant
    Filed: November 14, 2002
    Date of Patent: April 20, 2004
    Inventor: Arthur J. Bahmiller
  • Patent number: 6723181
    Abstract: A new soft stainless steel sheet has an austenite-stability index Md30 controlled in a range of −120 to −10 and a stacking fault formability index SFI controlled not less than 30, and involves precipitates whose Cu concentration is controlled not more than 1.0%, so as to maintain concentration of dissolved Cu at 1-5%. The stainless steel sheet preferably contains up to 0.06%(C+N), up to 2.0% Si, up to 5% Mn, 15-20% Cr, 5-9% Ni, 1.0-4.0% Cu, up to 0.003% Al, up to 0.005% S, and optionally one or more of up to 0.5% Ti, up to 0.5% Nb, up to 0.5% Zr, up to 0.5% V, up to 3.0% Mo, up to 0.03% B, up to 0.02% REM (rare earth metals) and up to 0.03% Ca. The stainless steel sheet can be plastically deformed to an objective shape without any cracks even at a part heavily-worked part by multi-stage deep drawing or compression deforming. Md30(° C.)=551−462(C+N)−9.2Si−8.1Mn−29(Ni+Cu)−13.7Cr−18.5Mo SFI(mJ/m2)=2.2Ni+6Cu−1.
    Type: Grant
    Filed: April 11, 2002
    Date of Patent: April 20, 2004
    Assignee: Nisshin Steel Co., Ltd.
    Inventors: Hanji Ishikawa, Masato Otsuka, Satoshi Suzuki, Hideki Tanaka, Junichi Katsuki, Takashi Yamauchi, Naoto Hiramatsu
  • Patent number: 6719855
    Abstract: The present invention provides an Fe—Cr—Al-based alloy for catalyst carriers and a foil thereof having a thickness of 40 &mgr;m or less, the alloy and the foil improved in the oxidation resistance at high temperatures and having excellent deformation resistance. Specifically, the present invention provides an Fe—Cr—Al-based alloy foil and a manufacturing method thereof, comprising 16.0 to 25.0 mass % of Cr, 1 to 8 mass % of Al, La, Zr, and the balance being Fe and incidental impurities. The contents by mass % of La and Zr meet the following ranges when the foil thickness thereof is t &mgr;m: 1.4/t≦La≦6.0/t  (1) 0.6/t≦Zr≦4.0/t  (2) The Fe—Cr—Al-based alloy foil may further comprises Hf and the balance being Fe and incidental impurities, wherein the contents by mass % of La, Zr, and Hf meet the following ranges: 1.4/t≦La≦6.0/t  (1) 0.4/t≦Zr≦2.0/t  (3) 0.5/t≦Hf≦2.0/t  (4).
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: April 13, 2004
    Assignee: JFE Steel Corporation
    Inventors: Kunio Fukuda, Susumu Satoh, Kazuhide Ishii, Takeshi Fujihira, Akira Kawaharada
  • Patent number: 6719854
    Abstract: There are provided a rolling bearing comprising an outer race, an inner race, and a plurality of rolling elements each interposed between the outer race and the inner race, at least one of the outer race, the inner race and the rolling elements being made of a steel consisting essentially, by mass, of 0.40 to 0.60% C, not more than 0.5% Si, not more than 0.5% Mn, not less than 8.0% but less than 10.0% Cr, and the balance Fe and incidental impurities, said steel having a hardness not less than 740 HV, carbides contained in said steel having a long size not more than 1.2 &mgr;m, and an amount of said carbides being not more than 3.5% in area %, and a method of producing the rolling bearing.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: April 13, 2004
    Assignee: Hitachi Metals Ltd.
    Inventors: Makoto Komori, Yasushi Tamura
  • Publication number: 20040065390
    Abstract: A low-cost ferritic steel sheet possessing not only formability enabling application to complexly configured automobile exhaust gas passage components but also high-temperature strength, high-temperature oxidation resistance and low-temperature toughness as good as or superior to existing ferritic steels, which ferritic steel sheet comprises, in mass percent, C: not more than 0.02%, Si: 0.7-1.1%, Mn: not more than 0.8%, Ni: not more than 0.5%, Cr: 8.0 to less than 11.0%, N: not more than 0.02%, Nb: 0.10-0.50%, Ti: 0.07-0.25%, Cu: 0.02-0.5%, B: 0.0005-0.02%, V: 0 (no addition)-0.20%, one or both of Ca and Mg: 0 (no addition)-0.01% in total, one or more elements among Y and rare earth elements: 0 (no addition)-0.20% in total, and the balance of Fe and unavoidable impurities, and satisfies 3Cr+40Si≧61, Cr+10Si≦21, and 420C−11.5Si+7Mn+23Ni−11.5Cr−12Mo+9Cu−49Ti−25(Nb+V)−52Al+470N+189≦70.
    Type: Application
    Filed: September 26, 2003
    Publication date: April 8, 2004
    Inventors: Manabu Oku, Yoshiaki Hori, Yoshitomo Fujimura, Takeshi Utsunomiya
  • Patent number: 6716291
    Abstract: A castable martensitic mold alloy and process for preparing same are disclosed. The composition is characterized by a ductile fine grain tempered martensite having an HRC of about 40 to about 50. The process includes forming a molten fixture of the components and then slow cooling same without requiring an additional tempering heat treatment step as is required in conventional techniques. The components comprise: a) from about 5.0-15% Cr; b) from about 0.5-15% Ni; c) from about 0.1-10% Mo; d) not more than about 2% Si; e) from about 0.1-2% Mn; f) from about 0.1-2% C; g) not more than about 1% S; h) not more than about 1% P; i) not more than about 5% B; j) and the balance being substantially Fe.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: April 6, 2004
    Assignee: Global Manufacturing Solutions, Inc.
    Inventor: Charles M. Woods
  • 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
  • Patent number: 6712913
    Abstract: A ferritic heat-resisting steel that shows a slight decrease in creep strength at the heat affected zone of the welded joint. The steel is characterized by consisting of, by mass %, C: less than 0.05%, Si: not more than 1.0%, Mn: not more than 2.0%, P: not more than 0.030%, S: not more than 0.015%, Cr: 7-14%, V: 0.05-0.40%, Nb: 0.01-0.10%, N: not less than 0.001% but less than 0.050%, sol. Al: not more than 0.010%, and O (oxygen): not more than 0.010%, with the balance being Fe and impurities, and further characterized in that the density of carbide and carbonitride precipitates contained with a grain diameter of not less than 0.3 &mgr;m is not more than 1×106/mm2. This steel may further contain one or more of the following elements: a total of 0.1-5.0% of Mo and W; a total of 0.02-5.00% of Cu, Ni and Co; a total of 0.01-0.20 of Ta, Hf, Nd and Ti; a total of 0.0005-0.0100% of Ca and Mg; and 0.0005-0.0100% of B.
    Type: Grant
    Filed: February 5, 2003
    Date of Patent: March 30, 2004
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Hiroyuki Hirata, Kazuhiro Ogawa
  • Patent number: 6712912
    Abstract: A weld filler metal alloy composition and a method for welding stainless steel components into a final assembly includes the steps of: austenitizing the stainless steel components to be welded at a temperature of 1800° F.-2000° F.; applying, using conventional arc welding techniques a solid wire of the filler metal alloy comprising in % by weight: up to 0.02% carbon; up to 0.8% manganese; up to 0.02% phosphorus; up to 0.015% sulfur; up to 0.6% silicon; 4.5-5.5% nickel; 0.4-0.7% molybdenum; 10-12.5% chromium; up to 0.1% copper; balance essentially iron and incidental impurities; and tempering the welded assembly welded at a temperature of 930° F.-1300° F. A second tempering step conducted at a temperature of 1095° F.-1145° F. may follow. The welding method can be used to make compressor impellers (6). The compressor impeller components comprise 13Cr-4Ni stainless steel.
    Type: Grant
    Filed: October 23, 2002
    Date of Patent: March 30, 2004
    Assignee: Elliott Turbomachinery Co., Inc.
    Inventors: Douglas K. Richards, Phillip Dowson
  • Publication number: 20040055674
    Abstract: A ferritic stainless steel sheet contains abut 0.01 percent by mass or less of carbon; about 1.0 percent by mass or less of silicon; about 1.5 percent by mass or less of manganese; about 11 to about 23 percent by mass of chromium; about 0.06 percent by mass or less of phosphorous; about 0.03 percent by mass or less of sulfur; about 1.0 percent by mass or less of aluminum; about 0.04 percent by mass or less of nitrogen; about 0.0005 to about 0.01 percent by mass of boron; about 0.3 percent by mass or less of vanadium; about 0.8 percent by mass or less of niobium and/or about 1.0 percent by mass or less of titanium wherein 18≦Nb/(C+N)+2(Ti/(C+N))≦60; and the balance being iron and unavoidable impurities. The average crystal grain diameter is about 40 &mgr;m or less and the average surface roughness is about 0.3 &mgr;m or less.
    Type: Application
    Filed: September 24, 2003
    Publication date: March 25, 2004
    Applicant: JFE Steel Corporation
    Inventors: Yoshihiro Yazawa, Osamu Furukimi, Yasushi Kato, Yoshihiro Ozaki
  • Patent number: 6709534
    Abstract: Carbon steels of high performance are disclosed that contain dislocated lath structures in which laths of martensite alternate with thin films of austenite, but in which each grain of the dislocated lath structure is limited to a single microstructure variant by orienting all austenite thin films in the same direction. This is achieved by careful control of the grain size to less than ten microns. Further improvement in the performance of the steel is achieved by processing the steel in such a way that the formation of bainite, pearlite, and interphase precipitation is avoided.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: March 23, 2004
    Assignee: MMFX Technologies Corporation
    Inventors: Grzegorz J. Kusinski, David Pollack, Gareth Thomas
  • Publication number: 20040050462
    Abstract: A ferritic stainless steel having improved high temperature mechanical properties includes greater than 25 weight percent chromium, 0.75 up to 1.5 weight percent molybdenum, up to 0.
    Type: Application
    Filed: June 24, 2003
    Publication date: March 18, 2004
    Inventor: John F. Grubb
  • Publication number: 20040035501
    Abstract: A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18≦Nb/(C+N)+2Ti/(C+N)≦60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.
    Type: Application
    Filed: August 25, 2003
    Publication date: February 26, 2004
    Applicant: Kawasaki Steel Corporation, a corporation of Japan
    Inventors: Yoshihiro Yazawa, Osamu Furukimi, Mineo Muraki, Yoshihiro Ozaki, Kunio Fukuda, Yukihiro Baba
  • Patent number: 6692585
    Abstract: Disclosed is a ferritic Fe—Cr—Ni—Al alloy having excellent oxidation resistance and high strength, which consists essentially of, by mass, 0.003 to 0.08% C, 0.03 to 2.0% Si, not more than 2.0% Mn, from more than 1.0% to not more than 8.0% Ni, from not less than 10.0% to less than 19.0% Cr, 1.5 to 8.0% Al, 0.05 to 1.0% Zr, and the balance of Fe and incidental impurities, wherein an F value is not less than 12% and an S value is not more than 25%, where the F value is defined by the following equation (1) and the S value is defined by the following equation (2): (1) F=−34.3C+0.48Si−0.012Mn−1.4Ni+Cr+2.48Al, and (2) S=Ni+Cr+Al. The Fe—Cr—Ni—Al alloy, after an annealing heat treatment at 600 to 1050° C., has 0.2% yield strength of 550 to 1,000 MPa by a tensile test at room temperature.
    Type: Grant
    Filed: December 4, 2001
    Date of Patent: February 17, 2004
    Assignee: Hitachi Metals Ltd.
    Inventors: Toshihiro Uehara, Yoshihiro Minagi, Kenichi Inoue
  • Patent number: 6689231
    Abstract: The invention relates to a ferrite-austenitic alloy and its use, the alloy has a composition with a mixture defined as: C maximum 0.05%, Si maximum 0.8%, Mn 0.30-1.5%, Cr 28.0-30.0%, Ni 5.80-7.40%, Mo 2.00-2.50%, N 0.30-0.40%, Cu maximum 1.0%, W maximum 2.0%, S maximum 0.010%, 30-70% ferrite and the balance austenite for tubes filled with hydraulic fluid, as transport tubes for solutions for chemical injection, or another uses in the application of umbilicals.
    Type: Grant
    Filed: June 21, 2000
    Date of Patent: February 10, 2004
    Assignee: Sandvik AB
    Inventor: Pasi Kangas
  • Patent number: 6689312
    Abstract: An alloy and article of manufacture including parts of glass container manufacturing apparatus such as a mold and plunger having a composition which consists of Carbon 0.1 to 0.5%, preferably 0.2 to 0.3% Silicon 0 to 2% preferably 0.5 to 1.5% Manganese 0 to 2% preferably 0.4 to 1.5% Sulphur 0.02 to 0.05% (an incidental element) Phosphorus 0.02 to 0.05% (an incidental element) Nickel 0 to 3% preferably 1.0 to 1.5% Chromium 5 to 35% preferably 15 to 20% Molybdenum 0 to 5% preferably 0.1 to 0.3% Copper 0 to 3% preferably 0.2 to 1% Boron 0.5 to 3.5% preferably 1.8 to 2.2%. The alloy and the articles of manufacture have having excellent high temperature characteristics and substantial hardenability.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: February 10, 2004
    Assignee: SG Alternatives, L.L.C.
    Inventor: Kenneth Donald Lakeland
  • Patent number: 6679954
    Abstract: The present invention makes the best use of a low-cost chemical composition in providing a high strength and high corrosion resistance stainless steel, which has improved delayed fracture resistance and toughness in particular, for building and construction uses, and as, for example, a stainless steel tapping screw. The present invention is, specifically, a stainless steel and a stainless steel screw with high strength and high toughness and excellent in delayed fracture resistance, characterized by: comprising, by mass, 0.01 to 0.25% of C, 0.05 to 1.0% of Si, 0.1 to 2.0% of Mn, 0.1 to 3.0% of Ni, 11.0 to 16.0% of Cr, 0.01 to 0.15% of N, and 0.01 to 3.0% of Mo; containing, optionally, 0.001 to 0.005% of B and/or one or more of 0.05 to 0.5% of Ti, 0.05 to 0.5% of Nb, and 0.05 to 0.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: January 20, 2004
    Assignee: Nippon Steel Corporation
    Inventors: Koji Takano, Takayoshi Matsui, Koichi Yoshimura
  • Patent number: 6673165
    Abstract: A high-hardness martensitic stainless steel excellent in corrosion resistance, comprising less than 0.15% by weight of C, from 0.10 to 1.0% by weight of Si, from 0.10 to 2.0% by weight of Mn, 0.010% or less of S, from 12.0 to 18.5% by weight of Cr, from 0.40 to 0.80% by weight of N, less than 0.030% by weight of Al, less than 0.020% by weight of O, and substantially the balance of Fe. The martensitic stainless steel of the present invention has cold-workability and hardness after tempering higher than that of SUS420J2 and corrosion resistance equivalent to or higher than that of an austenitic stainless steel SUS316.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: January 6, 2004
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Takeshi Koga, Tetsuya Shimizu, Toshiharu Noda
  • Patent number: 6663726
    Abstract: There are provided a high-hardness prehardened steel for cold working having excellent machinability containing, by mass, not less than 0.3% but less than 0.5% C, 0.7 to 2.0% Si, and 0.08 to 0.25% S, a die for cold working which is fabricated by cutting this prehardened steel at a cutting speed not less than 50 m/min. This steel is hardened and tempered to have a hardness not less than 50 HRC. Preferably, this steel consists, by mass, not less than 0.3% but less than 0.5% C, 0.7 to 2.0% Si, 0.1 to 2.0% Mn, 0.08 to 0.25% S, 0.5 to 15.0% Cr, at least one selected from the group consisting of W and Mo an amount of which one is not more than 3.5% in total in terms of (Mo+1/2W), not more than 4.0% V, not more than 0.15% N, and the balance Fe and incidental impurities.
    Type: Grant
    Filed: December 12, 2001
    Date of Patent: December 16, 2003
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yukio Abe, Hideshi Nakatsu, Yasushi Tamura, Yoshihiro Kada
  • Publication number: 20030217789
    Abstract: A martensitic stainless steel provided includes C: 0.01-0.
    Type: Application
    Filed: May 23, 2003
    Publication date: November 27, 2003
    Inventors: Mitsuru Yoshizawa, Kunio Kondo, Masaaki Igarashi, Yuichi Komizo
  • Patent number: 6645318
    Abstract: The present invention provides: a fuel tank made of a ferritic stainless steel sheet having long lasting corrosion resistance under the environment of the fuel tank and excellent in formability when fabricating the fuel tank; more specifically, a fuel tank made of a ferritic stainless steel sheet containing 10 to 25 mass % of Cr and having an average r-value of 1.9 or larger, an r-value in-plane anisotropy &Dgr;r of 1.0 or smaller, and a total elongation of 30% or larger, having a plane intensity ratio I(111)/I(100) of 10 or larger, and having lubricant films on the surfaces of the steel sheet and a surface friction coefficient of 0.10 or less.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: November 11, 2003
    Assignee: Nippon Steel Corporation
    Inventors: Akihiko Takahashi, Shunji Sakamoto, Yuji Koyama, Katsuhiko Kato, Tadashi Komori, Naoto Ono, Masayuki Abe
  • Patent number: 6641780
    Abstract: A ferritic stainless steel having improved high temperature mechanical properties includes greater than 25 weight percent chromium, 0.75 up to 1.5 weight percent molybdenum, up to 0.05 weight percent carbon, and at least one of niobium, titanium, and tantalum, wherein the sum of the weight percentages of niobium, titanium, and tantalum satisfies the following equation: 0.4≦(%Nb+%Ti+½(%Ta))≦1. The coefficient: of thermal expansion of the ferritic stainless steel is within 25 percent of the CTE of stabilized zirconia between 20° C. (68° F.) and 1000° C. (1832° F.), and the steel exhibits at least one creep property selected from creep rupture strength of at least 1000 psi at 900° C. (1,652° F.), time to 1% creep strain of at least 100 hours at 900° C. (1652° F.) under load of 1000 psi, and time to 2% creep strain of at least 200 hours at 900° C. (1652° F.) Under load of 1000 psi.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: November 4, 2003
    Assignee: ATI Properties Inc.
    Inventor: John F. Grubb
  • Patent number: 6635126
    Abstract: Steel alloys susceptible to case and core hardening comprising 0.05 to 0.24 weight percent carbon; 15 to 28 weight percent cobalt and 1.5 to 9.5 weight percent in nickel, small percentages of one or more additives: chromium, molybdenum, and vanadium; and the balance iron.
    Type: Grant
    Filed: November 25, 2002
    Date of Patent: October 21, 2003
    Assignee: Northwestern University
    Inventors: Charles J. Kuehmann, Gregory B. Olson, John P. Wise, Carelyn Campbell
  • Patent number: 6635128
    Abstract: A work-hardened poppet exhaust valve for internal combustion engines is obtained from a solutioned work-hardenable austenitic stainless steel coil or bar stock in which chromium is present in the range of 13%-25% by weight, nickel is present in the range of 4%-16% by weight, manganese is present in the range of 0.25%-8% by weight, copper is present in the range of 0.5%-7% by weight, the interstitial elements carbon plus nitrogen are present in a total amount less than 0.45% by nitrogen are present in a total amount less than 0.45% by weight, and at least one refractory metal selected from the group consisting of molybdenum, niobium, vanadium, tungsten and tantalum is present in the range of 1%-5% by weight. The coil or bar stock is extruded to a poppet valve preform configuration at a temperature in the range of room temperature to 1,000° F., and at a true strain of more than 0.8. The parameters of extrusion provide said work-hardened poppet valve with a stem hardness more than Rc=25.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: October 21, 2003
    Assignee: TRW Inc.
    Inventors: William Neumann, Roger R. Wills, Mohan Kurup, Victor Levin
  • Publication number: 20030188812
    Abstract: A ferritic heat-resistant steel, which exhibits excellent creep characteristics even at a high temperature exceeding 600° C., comprises, on the basis of percent by weight, 1.0 to 13% of chromium, 0.1 to 8.0% of cobalt, 0.01 to 0.20% of nitrogen, 3.0% or less of nickel, 0.01 to 0.50% of one or more of elements selected from a group consisting of vanadium, niobium, tantalum, titanium, hafnium, and zirconium that are MX type precipitate forming elements, and 0.01% or less of carbon and a balance being substantially iron and inevitable impurities, wherein the MX type precipitates precipitate on grain boundaries and in entire grains and the grain boundary existing ratio of an M23C6 type precipitate precipitating on the grain boundaries is 50% or less.
    Type: Application
    Filed: June 4, 2003
    Publication date: October 9, 2003
    Inventors: Masaki Taneike, Fujio Abe
  • Patent number: 6630103
    Abstract: A precipitation hardenable stainless steel having the following weight percent composition is disclosed. C 0.030 max. Mn  0.5 max. Si  0.5 max. P 0.040 max. S 0.025 max. Cr  9-13 Ni 7-9 Mo 3-6 Cu  0.75 max. Co  5-11 Ti  1.0 max. Al 1.0-1.5 Nb  1.0 max. B 0.010 max. N 0.030 max. O 0.020 max. The balance of the alloy is essentially iron and the usual impurities. One or more rare earth metals or calcium may be included in the alloy for removing and/or stabilizing phosphorus and sulfur. The alloy provides a unique combination of strength, toughness, and ductility. In accordance with another aspect of the present invention, there is described a useful article such as an aircraft structural component or a golf club head that is formed, at least in part, from the aforesaid alloy.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: October 7, 2003
    Assignee: CRS Holding, Inc.
    Inventors: James W. Martin, Theodore Kosa
  • Patent number: 6627007
    Abstract: A method has been developed for surface modifications of high temperature resistant alloys, such as FeCrAl alloys, in order to increase their resistance to corrosion at high temperatures. Coating it with a Ca-containing compound before heat-treating builds a continuos uniform and adherent layer on the surface of the alloy, that the aluminum depletion of the FeCrAl alloy is reduced under cyclic thermal stress. By this surface modification the resistance to high temperature corrosion of the FeCrAl alloy and its lifetime are significantly increased.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: September 30, 2003
    Assignee: Sandvik AB
    Inventors: Jan Andersson, Magnus Cedergren
  • Patent number: 6623569
    Abstract: A duplex stainless steel includes less than, in weight percent, 3 percent nickel and 1.5 percent molybdenum. In one embodiment, the duplex stainless steel includes, in weight percent, up to 0.06 percent carbon; 15 to 25 percent chromium; 1 to less than 2.5 percent nickel; greater than 2 percent up to 3.75 percent manganese; greater than 0.12 up to 0.35 percent nitrogen; up to 2 percent silicon; up to 1.5 percent molybdenum; up to 0.5 percent copper; up to 0.2 percent cobalt; up to 0.05 percent phosphorous; up to 0.005 percent sulfur; 0.001 to 0.0035 percent boron; iron and incidental impurities. The duplex stainless steel provided may be provided in the form of an article of manufacture, such as strip, bar, plate, sheet, casting, tubing or piping. A method for making the duplex stainless steel of the invention also is disclosed.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: September 23, 2003
    Assignee: ATI Properties, Inc.
    Inventors: David S. Bergstrom, John J. Dunn, John F. Grubb, William A. Pratt
  • Publication number: 20030172999
    Abstract: A ferritic-austenitic stainless steel having a microstructure which essentially consists of 35-65 vol-% ferrite and 35-65 vol-% austenitc has a chemical composition which contains in weight-%: 0.005-0.07 C, 0.1-2.0 Si, 3-8 Mn, 19-23 Cr, 0.5-1.7 Ni, optionally Mo and/or W in a total amount of max 1.0 (Mo+W/2), optionally Cu up to max 1.0 Cu, 0.15-0.30 N, balance iron and impurities. The following conditions shall apply for the chromium and nickel equivalents: 20<Creq<24.5, 10<Nieq, where (Creq=Cr+1.5 Si+Mo+2 Ti+0.5 Nb, and Nieq=Ni+0.5 Mn+30 (C+N)+0.5 (Cu+Co).
    Type: Application
    Filed: April 24, 2003
    Publication date: September 18, 2003
    Inventors: Elisabeth Alfonsson, Jun Wang, Mats Liljas, Per Johansson