Patents Assigned to Sumikin Stainless Steel Corporation
  • Patent number: 8894924
    Abstract: This ferrite stainless steel includes: by mass %, C: 0.020% or less; N: 0.025% or less; Si: 1.0% or less; Mn: 0.5% or less; P: 0.035% or less; S: 0.01% or less; Cr: 16% to 25%; Al: 0.15% or less; Ti: 0.05% to 0.5%; and Ca: 0.0015% or less, with the balance being Fe and inevitable impurities, wherein the following formula (1) is fulfilled, BI=3Al+Ti+0.5Si+200Ca?0.8??(1) (wherein Al, Ti, Si, and Ca in the formula (1) represent contents (mass %) of the respective components in the steel).
    Type: Grant
    Filed: February 5, 2010
    Date of Patent: November 25, 2014
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Tooru Matsuhashi, Michio Nakata
  • Patent number: 8878099
    Abstract: The present invention provides flux cored wire for welding duplex stainless steel which refines the solidified crystal grains for obtaining weld metal superior in toughness and ductility, characterized by containing, as the chemical ingredients included in the steel sheath and flux, by mass % with respect to the mass of the wire as a whole, C: 0.001 to 0.1%, Si: 0.01 to 1.0%, Mn: 2.0 to 6.0%, Cr: 17.0 to 27.0%, Ni: 1.0 to 10.0%, Mo: 0.1 to 3.0%, Al: 0.002 to 0.05%, Mg: 0.0005 to 0.01%, Ti: 0.001 to 0.5%, and N: 0.10 to 0.30%, further limiting P to 0.03% or less and S to 0.01% or less, satisfying 0.73×Cr equivalents?Ni equivalents?4.0 and Ti (mass %)×N (mass %)?0.0004, and having a balance of iron and unavoidable impurities.
    Type: Grant
    Filed: May 27, 2009
    Date of Patent: November 4, 2014
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Hiroshige Inoue, Manabu Mizumoto, Takashi Namekata, Yusuke Oikawa
  • Patent number: 8778260
    Abstract: The present invention provides duplex stainless steel superior in corrosion resistance in a chloride environment and impact properties suitable as a material for pumps for seawater desalination plants, facilities and equipment, and materials for chemical tanks, that is, duplex stainless steel characterized by containing, by mass %, C: 0.06% or less, Si: 0.05 to 3.0%, Mn: 0.1 to 6.0%, P: 0.05% or less, S: 0.010% or less, Ni: 1.0 to 10.0%, Cr: 18 to 30%, Mo: 5.0% or less, Cu: 3.0% or less, N: 0.10 to 0.40%, Al: 0.001 to 0.08% or less, Ti: 0.003 to 0.05%, Mg: 0.0001 to 0.0030%, and O: 0.010% or less, having a product of an activity coefficient fN of N, Ti content, and N content fN×Ti×N of 0.00004%2 or more, and having a product of Ti content and N content Ti×N of 0.008%2 or less.
    Type: Grant
    Filed: June 14, 2007
    Date of Patent: July 15, 2014
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Shinji Tsuge, Yuusuke Oikawa, Shigeo Fukumoto
  • Patent number: 8721960
    Abstract: The present invention provides a ferritic stainless steel comprised of, by mass %, C: 0.001 to 0.02%, Si: 0.01 to 0.6%, Mn: 0.01 to 0.6%, P: 0.005 to 0.04%, S: 0.0001 to 0.01%, Cr: 13 to 22%, N: 0.001 to 0.02%, Al: 0.005 to 0.05%, Sn: 0.001 to 1%, and a balance of Fe and unavoidable impurities, which steel satisfies the following formulae: 0<I(Fe)/I(Cr)<5 and 0<I(O)/I(Sn)<3, where I(Fe), I(Cr), I(Sn), and I(O) are the X-ray intensities of the Fe oxides, Cr oxides, Sn oxides, and the sum of X-ray intensities other detected oxides at the steel surface measured by an X-ray photoelectron spectrometer. The present invention also provides a method of producing the ferritic stainless steel.
    Type: Grant
    Filed: December 7, 2009
    Date of Patent: May 13, 2014
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Masaharu Hatano, Akihiko Takahashi, Eiichiro Ishimaru, Shigenori Takahata
  • Patent number: 8710405
    Abstract: A welding wire for austenitic stainless steel welding contains, in percent by mass, C: 0.005 through 0.05%, Si: 0.1 through 1.0%, Mn: 1.0 through 3.5%, Cr: 25.0 through 28.0%, Ni: 16.0 through 23.9%, Mo: 1.6 through 3.0%, Cu: 0.1 through 0.5%, Al: 0.001 through 0.02%, and N: more than 0.30 through 0.50%, limiting O to 0.03% or less, P to 0.03% or less, and S to 0.005% or less, and having a ratio of a Cr equivalent to Ni equivalent (Cr equivalent/Ni equivalent) within a range between 0.85 and 1.2 and a PI value of 35 or more, the remainder being iron and unavoidable impurities.
    Type: Grant
    Filed: April 13, 2006
    Date of Patent: April 29, 2014
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Hiroshige Inoue, Ryuichi Honma, Manabu Mizumoto, Yuusuke Oikawa, Ryo Matsuhashi, Shinji Tsuge, Shigeo Fukumoto
  • Publication number: 20140069619
    Abstract: An aspect of a ferritic stainless steel contains, by mass %: C: 0.03% or less; N: 0.03% or less; Si: more than 0.1% to 1% or less; Mn: 0.02% to 1.2%; Cr: 15% to 23%; Al: 0.002% to 0.5%; and either one or both of Nb and Ti, with the remainder being Fe and unavoidable impurities, wherein Expression (1) and Expression (2) illustrated below are satisfied, an oxide film is formed on a surface thereof, and the oxide film contains Cr, Si, Nb, Ti and Al in a total cationic fraction of 30% or more, 8(C+N)+0.03?Nb+Ti?0.6??(1) Si+Cr+Al+{Nb+Ti?8(C+N)}?15.5??(2).
    Type: Application
    Filed: March 28, 2012
    Publication date: March 13, 2014
    Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATION
    Inventors: Nobuhiko Hiraide, Fumio Fudanoki, Shunji Sakamoto
  • Patent number: 8628631
    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. The present invention is characterized in that the average composition of the Mg containing oxides dispersing in a casting satisfies the following expressions <2> and <3>, 17.4(Al2O3)+3.9(MgO)+0.3(MgAl2O4)+18.7(CaO)?500??<2>, (Al2O3)+(MgO)+(MgAl2O4)+(CaO)?95??<3>.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: January 14, 2014
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Akihiko Takahashi, Junichi Hamada, Ken Kimura, Takashi Morohoshi, Yoshihito Yamada, Toyohiko Kakihara, Satoshi Hashimoto
  • Patent number: 8623502
    Abstract: This clear-coated stainless steel sheet includes: a stainless steel sheet; and a clear-coated film coated on either one or both of two main surfaces of the stainless steel sheet, wherein the clear-coated film contains a thermosetting resin composition (A) and resin beads (B) at a content in a range of 0.5 parts by mass to 4.0 parts by mass relative to 100 parts by mass of a solid content of the thermosetting resin composition (A), the thermosetting resin composition (A) includes an acrylic resin (A1) and a cross-linked curing resin (A2) composed of a blocked isocyanate resin and an amino resin which cross-link and cure the acrylic resin (A1), the acrylic resin (A1) includes one or more cross-linking functional groups selected from a hydroxyl group, a carboxylic group, and an alkoxy silane group, and the acrylic resin (A1) has a glass transition temperature of 30° C. to 90° C., and has a number average molecular weight of 3000 to 50000.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: January 7, 2014
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Hiroyuki Matsuyama, Haruki Ariyoshi, Youichirou Yasuda
  • Publication number: 20130336834
    Abstract: The present invention provides austenitic stainless steel which is not only excellent in brazeability, but is also excellent in corrosion resistance in an environment where condensation of combustion exhaust gas causes formation of condensed water which contains nitric acid ions or sulfuric acid ions and which is low in pH or in an environment of an aqueous solution which contains chloride ions, which contains, by mass %, C: 0.080% or less, Si: 1.2 to 3.0%, Mn: 0.4 to 2.0%, P: 0.03% or less, S: 0.003% or less, Ni: 6.0 to 12.0%, Cr: 16.0 to 20.0%, Cu: 0.2 to 3.0%, Al: 0.002 to 0.10%, N: 0.030 to 0.150%, and Mo: 0.1 to 1.0%, has a balance of Fe and unavoidable impurities, and satisfies Formula (A): 1.6?[Cu]×[Si?]4.4 and Formula (B): 0.16?2[N]+[Mo?]1.0.
    Type: Application
    Filed: March 28, 2012
    Publication date: December 19, 2013
    Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATION
    Inventors: Tooru Matsuhashi, Jun Tokunaga
  • Publication number: 20130337289
    Abstract: The present invention provides an alloy-saving type high purity ferritic stainless steel sheet not relying on high alloying of addition giving a large content of at least one of Cr and No and further not limited to a surface film by bright annealing and utilizing addition of Sn to doubly provide an anti-glare property and corrosion resistance, comprising steel sheet which contains, by mass %, C: 0.001 to 0.03%, Si: 0.01 to 1%, Mn: 0.01 to 1.5%, P: 0.005 to 0.05%, S: 0.0001 to 0.01%, Cr: 13 to 30%, N: 0.001 to 0.03%, Al: 0.005 to 1%, and Sn: 0.01 to 1% and has a balance of Fe and unavoidable impurities and which has a surface film, the surface film containing one or both of Al and Si in a total of 5 to 50 at % and Sn and an average concentration of Cr in the surface film being 1.1 to 3 times the concentration of Cr inside the steel sheet, and the surface film having a surface roughness of an arithmetic average roughness Ra of 0.1 to 1.5 ?m.
    Type: Application
    Filed: March 5, 2012
    Publication date: December 19, 2013
    Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATION
    Inventors: Masaharu Hatano, Hiroyuki Matsuyama, Akihito Yamagishi, Naoto Hansaki, Eiichiro Ishimaru
  • Publication number: 20130319583
    Abstract: The present invention provides a low-alloy high-purity ferritic stainless steel sheet provided with improved oxidation resistance and high-temperature strength by utilizing Sn addition in trace amounts without relying on excessive alloying of Al and Si which reduces fabricability and weldability or addition of rare elements such as Nb, Mo, W, and rare earths, and a process for producing the same. The high-purity ferritic stainless steel sheet includes C: 0.001 to 0.03%, Si: 0.01 to 2%, Mn: 0.01 to 1.5%, P: 0.005 to 0.05%, S: 0.0001 to 0.01%, Cr: 16 to 30%, N: 0.001 to 0.03%, Al: 0.05 to 3%, and Sn: 0.01 to 1% (% by mass), with the remainder being Fe and unavoidable impurities. A stainless steel slab having such steel components is heated, wherein an extraction temperature is 1100 to 1250° C., and a winding temperature after hot rolling is 650° C. or lower. A hot-rolled sheet is annealed at 900 to 1050° C., and cooled at 10° C./sec or less over a temperature range of 550 to 850° C.
    Type: Application
    Filed: January 23, 2012
    Publication date: December 5, 2013
    Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATION
    Inventors: Masaharu Hatano, Eiichiro Ishimaru, Akihiko Takahashi
  • Publication number: 20130306204
    Abstract: This hot-rolled ferritic stainless steel sheet has a steel composition containing, in terms of % by mass: 0.02% or less of C; 0.02% or less of N; 0.1% to 1.5% of Si; 1.5% or less of Mn; 0.035% or less of P; 0.010% or less of S; 1.5% or less of Ni; 10% to 20% of Cr; 1.0% to 3.0% of Cu; 0.08% to 0.30% of Ti; and 0.3% or less of Al, with the balance being Fe and unavoidable impurities, and the hot-rolled ferritic stainless steel sheet has a Vickers hardness of less than 235 Hv.
    Type: Application
    Filed: February 8, 2012
    Publication date: November 21, 2013
    Applicant: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Shinichi Teraoka, Masaaki Kobayashi, Yuuji Koyama, Junichi Hamada, Norihiro Kanno, Yoshiharu Inoue, Ken Kimura, Jun Takahashi, Shigeyuki Gotoh
  • Patent number: 8506729
    Abstract: An austenitic stainless steel hot-rolled steel material can be provided which has sea-water resistance and strength superior to conventional steel. Low-temperature toughness can be maintained, which is preferable in a structural member of speedy craft. The steel material can include an austenitic stainless steel hot-rolled steel material which excels in the properties of corrosion resistance, proof stress, and low-temperature toughness. In such austenitic stainless steel hot-rolling steel material, e.g., PI [=Cr+3.3(Mo+0.5W)+16N] ranges from 35 to 40, ? cal [=2.9 (Cr+0.3Si+Mo+0.5W)?2.6 (Ni+0.3Mn+0.25Cu+35C+20N)?18] ranges from ?6 to +2, and a 0.2% proof stress at room temperature is not less than 550 MPa, Charpy impact value measured using a V-notch test piece at ?40° C. is not less than 100 J/cm2, and the pitting potential measured in a deaerated aqueous solution of 10% NaCl at 50° C. (Vc?100) is not less than 500 mV (as it relates to saturated Ag/AgCl).
    Type: Grant
    Filed: January 13, 2012
    Date of Patent: August 13, 2013
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Yuusuke Oikawa, Shinji Tsuge, Shigeo Fukumoto, Kazuhiro Suetsugu, Ryo Matsuhashi, Hiroshige Inoue
  • Patent number: 8500923
    Abstract: The present invention provides a stainless steel as a metal base material for a weight sensor substrate of an automobile airbag. The stainless steel sheet contains a high aluminiferous ferritic stainless steel containing, in mass, Al of 2.5 to 8%, C: 0.025% or less, N: 0.025% or less, the sum of C and N being 0.030% or less, and Nb: 0.05 to 0.5%, with the balance Fe and unavoidable impurities. Said stainless steel sheet may further contain, in mass, one or more of V: 0.05 to 0.4%, Ti: 0.02 to 0.2%, and Zr: 0.02 to 0.2%. The present invention controls the difference in the average linear expansion coefficient between said stainless steel sheet and crystallized glass for said weight sensor to less than 10% in the temperature range from 20° C. to 900° C. and thus to improve the adhesiveness of said stainless steel sheet with said crystallized glass.
    Type: Grant
    Filed: May 14, 2008
    Date of Patent: August 6, 2013
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Masuhiro Fukaya, Tadashi Komori
  • Publication number: 20130174949
    Abstract: Inexpensive stainless steel and inexpensive and high strength stainless steel which has excellent hydrogen environment embrittlement resistance even if used in a hydrogen resistant environment in over 40 MPa high pressure hydrogen gas or a hydrogen resistant environment in liquid hydrogen, characterized by containing, by mass %, C: 0.1% or less, Si: 0.4 to 1.5%, Mn: 8 to 11%, Cr: 15 to 17%, Ni: 5 to 8%, Cu: 1 to 4%, and N: 0.01 to less than 0.15% and having a balance of Fe and unavoidable impurities, having a volume rate of ?-ferrite of 10% or less, and having a long axis of ?-ferrite before annealing of 0.04 to 0.1 mm.
    Type: Application
    Filed: September 29, 2011
    Publication date: July 11, 2013
    Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATION
    Inventors: Masaharu Hatano, Shigeo Fukumoto, Hideki Fujii, Shinichi Ohmiya
  • Patent number: 8470237
    Abstract: The stainless steel of the first embodiment includes C: 0.001 to 0.02%, N: 0.001 to 0.02%, Si: 0.01 to 0.5%, Mn: 0.05 to 0.5%, P: 0.04% or less, S: 0.01% or less, Ni: more than 3% to 5%, Cr: 11 to 26%, and either one or both of Ti: 0.01 to 0.5% and Nb: 0.02 to 0.6%, and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the second embodiment has an alloy composition different from those of the first and third embodiments and satisfies the formula (A): Cr+3Mo+6Ni?23 and formula (B): Al/Nb?10 and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the third embodiment has an alloy composition different from those of the first and second embodiments and includes either one or both of Sn: 0.005 to 2% and Sb: 0.005 to 1% and contains as the remainder, Fe and unavoidable impurities.
    Type: Grant
    Filed: May 8, 2007
    Date of Patent: June 25, 2013
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Nobuhiko Hiraide, Haruhiko Kajimura, Ken Kimura
  • Patent number: 8444916
    Abstract: The stainless steel of the first embodiment includes C: 0.001 to 0.02%, N: 0.001 to 0.02%, Si: 0.01 to 0.5%, Mn: 0.05 to 0.5%, P: 0.04% or less, S: 0.01% or less, Ni: more than 3% to 5%, Cr: 11 to 26%, and either one or both of Ti: 0.01 to 0.5% and Nb: 0.02 to 0.6%, and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the second embodiment has an alloy composition different from those of the first and third embodiments and satisfies the formula (A): Cr+3Mo+6Ni?23 and formula (B): Al/Nb?10 and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the third embodiment has an alloy composition different from those of the first and second embodiments and includes either one or both of Sn: 0.005 to 2% and Sb: 0.005 to 1% and contains as the remainder, Fe and unavoidable impurities.
    Type: Grant
    Filed: May 8, 2007
    Date of Patent: May 21, 2013
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Nobuhiko Hiraide, Haruhiko Kajimura, Ken Kimura
  • Publication number: 20130074971
    Abstract: A fuel pipe which is inexpensive and is excellent in salt spray corrosion resistance, characterized by being comprised of a steel pipe member having as a material a ferritic stainless steel which contains, by mass %, C: 0.015% or less, Si: 0.01 to 0.50%, Mn: 0.01 to 0.50%, P: 0.050% or less, S: 0.010% or less, N: 0.015% or less, Al: 0.010 to 0.100%, and Cr: 13.0 to 18.0% and further, one or both of Ti: 0.03 to 0.30% and Nb: 0.03 to 0.30% and a metal fitting part, the metal fitting part and the steel pipe member having between them a crevice structure at the surface which the structure is exposed to a salt spray environment, an opening amount at a crevice part of the crevice structure being 0.2 mm or more, and an inside of the crevice part being coated by electrodeposition.
    Type: Application
    Filed: June 3, 2011
    Publication date: March 28, 2013
    Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATION
    Inventors: Shunji Sakamoto, Toshio Tanoue
  • Publication number: 20130014864
    Abstract: High strength dual-phase structure stainless steel sheet and steel strip which are excellent in corrosion resistance, the dual-phase structure stainless steel sheet and steel strip having a Vicker's hardness of 200 HV or more and characterized by containing, by mass %, C: 0.02 to 0.20%, Si: 0.10 to 2.0%, Mn: 0.20 to 2.0%, P: 0.040% or less, S: 0.010% or less, Cr: 15.0 to 18.0%, Ni: 0.5 to 4.0%, Sn: 0.05 to 0.50, and N: 0.010 to 0.10%, having a ?p of 60 to 95 in range, having a balance of substantially Fe, and having a ferrite and martensite dual-phase structure formed by being heated to the ferrite and austenite dual-phase region, then the austenite phase transforming to martenite in the subsequent cooling process, where ?p=420C+470N+23Ni+7Mn+9Cu?11.5Cr?11.5Si?12Mo?7Sn?49Ti?47Nb?52Al+189.
    Type: Application
    Filed: March 29, 2011
    Publication date: January 17, 2013
    Applicant: NIPPON STEEL & SUMIKIN STAINLESS STEEL CORPORATION
    Inventors: Shinichi Teraoka, Shunji Sakamoto
  • Patent number: 8303733
    Abstract: This stainless steel sheet includes, in terms of mass %, C: 0.001 to 0.1%, N: 0.01 to 0.15%, Si: 0.01 to 2%, Mn: 0.1 to 10%, P: 0.05% or less, S: 0.01% or less, Ni: 0.5 to 5%, Cr: 10 to 25%, and Cu: 0.5 to 5%, with a remainder being Fe and unavoidable impurities, and contains a ferrite phase as a main phase and 10% or more of an austenite phase, wherein a work-hardening rate in a strain range of up to 30% is 1000 MPa or more which is measured by a static tensile testing and a difference between static and dynamic stresses which occur when 10% of deformation is caused is 150 MPa or more. This method for producing a stainless steel includes annealing a cold-rolled steel sheet under conditions where a holding temperature is set to be in a range of 950 to 1150° C. and a cooling rate until 400° C. is set to be in a range of 3° C./sec or higher.
    Type: Grant
    Filed: January 22, 2009
    Date of Patent: November 6, 2012
    Assignee: Nippon Steel & Sumikin Stainless Steel Corporation
    Inventors: Junichi Hamada, Haruhiko Kajimura, Eiichiro Ishimaru