Patents Assigned to Daido Tokushuko Kabushiki Kaisha
  • Patent number: 6921442
    Abstract: The present invention relates to a Ni base alloy having sufficient strength at high temperatures and high corrosion resistance at high temperatures in a high-temperature composite corrosive environment in which chlorination or sulfidation occurs simultaneously with high-temperature oxidation, without excessive cooling or surface protection. According to the present invention, a Ni base alloy having high-temperature strength and corrosion resistance includes Cr in a range of from 25 to 40 weight %, Al in a range of from 1.5 to 2.5 weight %, C in a range of from 0.1 to 0.5 weight %, W of 15 weight % or less, Mn of 2.0 weight % or less, Si in a range of from 0.3 to 6 weight %, Fe of 5% or less, and Ni of rest except inevitable impurities. When strength at high temperatures is allowed to be small, W is in a range of from 0 to 8%, and Si is in a range of from 0.3 to 1% or from 1 to 6%. In order to enhance strength at high temperatures, W is in a range of from 8 to 15, and Si is in a range of from 0.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: July 26, 2005
    Assignees: Ebara Corporation, Daido Tokushuko Kabushiki Kaisha
    Inventors: Manabu Noguchi, Kei Matsuoka, Hiroshi Yakuwa, Akira Uchino, Hideyuki Sakamoto, Michio Okabe, Yoshiyuki Sawada, Shigeki Ueta
  • Patent number: 6918972
    Abstract: A Ni-base alloy which has excellent resistance to permanent set at high temperature and which can be produced at low cost, a heat-resistant spring made of the Ni-base alloy, and a process for producing the spring. The Ni-base alloy of the present invention consists of 0.01 to 0.15 mass % of C, 2.0 mass % or less of Si, 2.5 mass % or less of Mn, 12 to 25 mass % of Cr, 5.0 mass % or less of Mo and/or 5.0 mass % or less of W on condition that Mo+W/2 does not exceed 5.0 mass % or less, 1.5 to 3.5 mass % of Ti, 0.7 to 2.5 mass % of Al, 20 mass % or less of Fe, and the balance of Ni and unavoidable impurities. The ratio of Ti/Al in terms of atomic percentage ranges from 0.6 to 1.5 and the total content of Ti and Al ranges from 4.0 to 8.5 atomic %.
    Type: Grant
    Filed: February 20, 2003
    Date of Patent: July 19, 2005
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Shigeki Ueta, Toshiharu Noda
  • Publication number: 20050098240
    Abstract: A ferritic free-cutting stainless steel excellent in surface roughness and outgass resistance is disclosed which comprises in weight percentage, 0.06% or less of C, 0.05 to 1.0% of Si, 2.0% or less of Mn, 0.050% or less of P, 0.05 to 0.50% of S, 2.0% or less of Cu, 2.0% or less of Ni, 9.0 to 25.0% of Cr, 4.0% or less of Mo, 0.065 to 2.0% of Ti, 0.0150% or less of 0, 0.020% or less of N, 0.001 to 0.100% of Al, and Fe and inevitable impurity in the rest portion, wherein the steel satisfies Equations (1) and (2) of the equations, [Ti]?1.3×[S]??Equation (1) [Mn]/[Ti]?3??Equation (2) (WTi+WCr) >2×WMn??Equation (3) where the amount of Ti contained in the steel is represented by [Ti], that of S is represented by [S] and that of Mn is represented by [Mn], and wherein the steel satisfies Equation (3) where the amount of Ti contained in sulfide produced in the texture of the steel is represented by WTi, that of Cr is represented by WCr and that of Mn is represented by WMn.
    Type: Application
    Filed: November 9, 2004
    Publication date: May 12, 2005
    Applicant: Daido Tokushuko Kabushiki Kaisha
    Inventors: Koichi Ishikawa, Tetsuya Shimizu
  • Publication number: 20050030217
    Abstract: An electromagnetic wave absorber having an excellent electromagnetic wave absorption characteristic in 5 to 6 GHz band. The electromagnetic wave absorber has a matrix and powder filled in the matrix. The particles of the powder have electrical conductivity at least in surface regions thereof and have a particle diameter of 3 to 20 ?m as expressed by D50 value. A volumetric ratio (V) in which the powder is filled in the matrix is set such that a standardized value expressed as a value obtained by dividing a complex relative permeability (??) of the electromagnetic wave absorber in a frequency band to be absorbed thereby by the volumetric ratio (V) is constant as far as the particle diameter of the powder used, as expressed by the D50 value, is within the range of 3 to 20 ?m.
    Type: Application
    Filed: June 29, 2004
    Publication date: February 10, 2005
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Akihiko Saito, Nobuaki Tanaka
  • Patent number: 6852174
    Abstract: There is disclosed a powder magnetic core in which a permeability does not easily drop even when an applied magnetic field intensifies, comprising: a bulk body containing a main component of a powder of an Fe-base alloy having a soft magnetic property, and the balance substantially including a heat-treated insulation binder and a void, wherein an aspect ratio of the powder is in a range of 1 to 1.5, and a volume ratio of the powder in the bulk body is in a range of 40 to 60 volume %, and an initial permeability (?0) has a value which satisfies 6??0?20, and a relation of ?/?0?0.5 is established between K and A, when the permeability is ? with an applied magnetic field of 24 kA/m.
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: February 8, 2005
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Satoshi Takemoto, Takanobu Saito
  • Publication number: 20050011589
    Abstract: Provided is free cutting alloy excellent in machinability, preserving various characteristics as alloy. The free cutting alloy contains: one or more of Ti and Zr as a metal element component; and C being an indispensable element as a bonding component with the metal element component, wherein a (Ti,Zr) based compound including one or more of S, Se and Te is formed in a matrix metal phase. The free cutting alloy is more excellent in machinability, preserving various characteristics as alloy at similar levels to a conventional case. The effect is especially conspicuous, for example, when a compound expressed in a chemical form of (Ti,Zr)4C2(S,Se,Te)2 as the (Ti,Zr) based compound is formed at least in a dispersed state in the alloy structure.
    Type: Application
    Filed: May 18, 2004
    Publication date: January 20, 2005
    Applicants: Kiyohito Ishida, Katsunari Oikawa, Daido Tokushuko Kabushiki Kaisha, Tohoku Tokushuko Kabushiki Kaisha, Japan Industrial Technology Association, Tohoku Technoarch Co., Ltd.
    Inventors: Kiyohito Ishida, Katsunari Oikawa, Takashi Ebata, Takayuki Inoguchi, Tetsuya Shimizu, Michio Okabe
  • Publication number: 20050000602
    Abstract: Provided is free cutting alloy excellent in machinability, preserving various characteristics as alloy. The free cutting alloy contains: one or more of Ti and Zr as a metal element component; and C being an indispensable element as a bonding component with the metal element component, wherein a (Ti,Zr) based compound including one or more of S, Se and Te is formed in a matrix metal phase. The free cutting alloy is more excellent in machinability, preserving various characteristics as alloy at similar levels to a conventional case. The effect is especially conspicuous, for example, when a compound expressed in a chemical form of (Ti,Zr)4C2(S,Se,Te)2 as the (Ti,Zr) based compound is formed at least in a dispersed state in the alloy structure.
    Type: Application
    Filed: May 18, 2004
    Publication date: January 6, 2005
    Applicants: Kiyohito ISHIDA, Katsunari OIKAWA, Daido Tokushuko Kabushiki Kaisha, Tohoku Tokushuko Kabushiki Kaisha, Japan Industrial Technology Association, Tohoku Technoarch Co., Ltd.
    Inventors: Kiyohito Ishida, Katsunari Oikawa, Takashi Ebata, Tetsuya Shimizu, Michio Okabe
  • Patent number: 6761853
    Abstract: A free-cutting tool steel is provided containing Fe and C in an amount of 0.1 to 2.5 wt %, Ti and or Zr where WTi+0.52WZr constitutes 0.03 to 3.5 wt %, and WTi represents Ti content and WZr represents Zr content, at least any one of S, Se and Te where WS+0.4WSe+0.25WTe constitutes 0.01 to 1.0 wt %, and (WTi+0.52WZr)/(WS+0.4WSe+0.25WTe) constitutes 1 to 4, and WS represents S content, WSe represents Se content and WTe represents Te content; and dispersed therein a texture thereof from 0.1 to 10% in terms of area ratio in a section of a machinability improving compound phase of a metallic element component of Ti and/or Zr as major components, and a binding component for the metallic element component containing C and any one of S, Se and Te.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: July 13, 2004
    Assignees: Dokuritsu Gyousei Houjin Sangyo Gijutsu Sougo Kenkyusho, Daido Tokushuko Kabushiki Kaisha
    Inventors: Kiyohito Ishida, Katsunari Oikawa, Toshimitsu Fujii, Yukinori Matsuda, Kozo Ozaki, Seiji Kurata, Takayuki Shimizu
  • Patent number: 6756011
    Abstract: A high-strength, high corrosion-resistant and non-magnetic stainless steel which is further excellent in strength and corrosion resistance and safe in the living body and also can stand against various corrosive environments. The stainless steel comprises 0.15% by weight or less of C, 1.0% or less of Si, 3.0 to 12.0% of Mn, 0.030% or less of P, 0.50% or less of Ni, 15.0 to 21.0% of Cr, 0.70 to 1.50% of N, 0.020% or less of Al and 0.020% or less of O, and a remainder of Fe and inevitable impurities.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: June 29, 2004
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Takeshi Koga, Tetsuya Shimizu, Toshiharu Noda
  • Patent number: 6752883
    Abstract: A free-cutting Ni-base heat-resistant alloy excellent in the high-temperature strength and corrosion resistance was proposed. The alloy contains Ni as a major component, 0.01 to 0.3 wt % of C and 14 to 35 wt % of Cr, and further contains at least one element selected from Ti, Zr and Hf in a total amount of 0.1 to 6 wt %, and S in an amount of 0.015 to 0.5 wt %. The alloy has dispersed in the matrix thereof a machinability improving compound phase, where such phase contains any one of Ti, Zr and Hf as a major constituent of the metal elements, essentially contains C and either S or Se as a binding component for such metal elements. The alloy also satisfies the relations of WTi+0.53WZr+0.27WHf>2WC+0.75WS and WC>0.37WS, where WTi represents Ti content (wt %), WZr represents Zr content (wt %), WHf represents Hf content (wt %), WC represents C content (wt %) and WS represents S content (wt %).
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: June 22, 2004
    Assignees: Dokuritsu Gyousei Houjin Sangyo Gijutsu Sougo Kenkyusho, Daido Tokushuko Kabushiki Kaisha, Tohoku Tokushuko Kabushiki Kaisha
    Inventors: Kiyohito Ishida, Katsunari Oikawa, Shigeki Ueta, Toshiharu Noda, Takashi Ebata
  • Publication number: 20040056012
    Abstract: A welding wire contains 0.025 mass % or less C, 1.3 mass % or less Si, 2.0 mass % or less Mn, 10 to 25 mass % Cr, 0.04 to 0.2 mass % N, Al and Ti in amounts (mass %) satisfying the relationship: e−800(x−0.05)2×e−300(y−0.08)2≧0.5, where x and y represent contents (mass %) of Al and Ti, respectively, O in an amount (mass %) satisfying the relationship: z<(x+y−0.01)/0.5, where z represents a total amount (mass %) of oxygen in the welding wire, and the balance being Fe and unavoidable impurities. Gas-shielded welding is performed using the welding wire and a shielding gas containing Ar and at least one of O2 and CO2, wherein, provided that volume % of the O2 and CO2 contained in the shielding gas are p and q, respectively, the shielding gas satisfies the relationships: p≦10; q≦50; and p+q≦(x+y−0.01−0.5z)/0.0006, whereby a weld improved in high-temperature resistance and crack resistance can be formed.
    Type: Application
    Filed: June 16, 2003
    Publication date: March 25, 2004
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Keigo Inui, Hirotaka Minamikawa, Toshiharu Noda
  • Publication number: 20040045697
    Abstract: A molten steel of a special steel or the like including a high-alloy steel is poured in a mold whose bottom portion is closed with a dummy head of a lift table. As the lift table is vertically moved down at a given casting speed, a casting whose lower end is supported by the dummy head is continuously pulled out from the bottom portion of the mold. As a pair of movable molds that constitute the mold are relatively moved away from each other in synchronism with the downward movement of the lift table, both widthwise side surfaces of the casting are provided with required tapering.
    Type: Application
    Filed: August 12, 2003
    Publication date: March 11, 2004
    Applicant: Daido Tokushuko Kabushiki Kaisha
    Inventors: Hajime Takahashi, Hajime Amano, Soichiro Kumura
  • Patent number: 6699593
    Abstract: A highly corrosion-resistant material and a corrosion-resistant member which are improved in corrosion resistance, adhesion, contact electrical resistance, electrical conductivity, airtightness, etc. and are suitable for use as, e.g., a metallic separator for polymer electrolyte fuel cells (PEFC); and a process for producing them. A thin noble-metal layer is formed on the desired part of the surface of a metallic base and then subjected to compression working. The coated base may further be subjected to anticorrosive treatment with a liquid phase containing a peroxide or ozone or with an active gas atmosphere.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: March 2, 2004
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Yasushi Kaneta, Shinobu Takagi, Hiroaki Yoshida, Yoshihisa Suzuki, Masaki Shinkawa
  • 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
  • Publication number: 20030164213
    Abstract: A Ni-base alloy which has excellent resistance to permanent set at high temperature and which can be produced at low cost, a heat-resistant spring made of the Ni-base alloy, and a process for producing the spring. The Ni-base alloy of the present invention consists of 0.01 to 0.15 mass % of C, 2.0 mass % or less of Si, 2.5 mass % or less of Mn, 12 to 25 mass % of Cr, 5.0 mass % or less of Mo and/or 5.0 mass % or less of W on condition that Mo+W/2 does not exceed 5.0 mass % or less, 1.5 to 3.5 mass % of Ti, 0.7 to 2.5 mass % of Al, 20 mass % or less of Fe, and the balance of Ni and unavoidable impurities. The ratio of Ti/Al in terms of atomic percentage ranges from 0.6 to 1.5 and the total content of Ti and Al ranges from 4.0 to 8.5 atomic %.
    Type: Application
    Filed: February 20, 2003
    Publication date: September 4, 2003
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Shigeki Ueta, Toshiharu Noda
  • Publication number: 20030155047
    Abstract: A low thermal expansion Ni-base superalloy contains, by weight % (hereinafter the same as long as not particularly defined) C: 0.15% or less; Si: 1% or less; Mn: 1% or less; Cr: 5 to 20%; at least one of Mo, W and Re of Mo+½ (W+Re) of 17 (exclusive) to 25%; Al: 0.2 to 2%; Ti: 0.5 to 4.5%; Fe of 10% or less; at least one of B: 0.02% and Zr: 0.2% or less; a remainder of Ni and inevitable impurities; wherein the atomic % of Al+Ti is 2.5 to 7.0.
    Type: Application
    Filed: September 27, 2002
    Publication date: August 21, 2003
    Applicants: Daido Tokushuko Kabushiki Kaisha, Mitsubishi Heavy Industries, Ltd.
    Inventors: Ryotaro Magoshi, Hisataka Kawai, Yoshikuni Kadoya, Ryuichi Yamamoto, Toshiharu Noda, Susumu Isobe, Michio Okabe
  • Patent number: 6606895
    Abstract: Described is a method of manufacturing a crown-shaped component 3 having a plurality of axially extending protrusions 2 which are formed at an end of a cylindrical portion 1. The method comprises the steps of: upsetting the cylindrical portion into a cylindrical blank 10a having protrusions arrayed on and along the inner circumferential surface of a remaining part 12; annealing the cylindrical blank; removing the remaining part by cutting; and subjecting the resultant blank to a shot blasting process, whereby a magnetic characteristic of the resultant crown-shaped component is improved.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: August 19, 2003
    Assignees: Koyo Seiko Co., Ltd., Daido Tokushuko Kabushiki Kaisha
    Inventors: Takahiro Sanada, Yoshiro Sakai, Narito Shimizu, Jun Yatazawa, Shigeru Iwasa
  • Patent number: 6605162
    Abstract: This invention relates to an anisotropic magnet having excellent magnetic characteristics such as a high magnetic flux density, a process for producing the same, and a motor having the same.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: August 12, 2003
    Assignees: Nissan Motor Co., Ltd., Daido Tokushuko Kabushiki Kaisha
    Inventors: Hideaki Ono, Munekatsu Shimada, Norihisa Waki, Akira Fujiki, Takahiko Iriyama
  • Patent number: 6592154
    Abstract: In diffusion bonding a metal pipe 112e and a metal pipe 114e via a bonded interface 116e formed at the end parts, a portion that is inclined with respect to the radial direction of metal pipes 112e and 114e is provided at least at part of bonded interface 116. In this case, the inclination angle &phgr; of bonded interface 116e and the tip angle 2&thgr; of a pipe expansion tool 130 are preferably in the relationship, 0<&phgr;≦&thgr;+60°. In performing pipe expansion of such a metal pipe bonded body 110e, the pipe expansion tool 130 is moved from the metal pipe 112e, at which the inclined portion of junction face 116e is formed to have a protruding shape, towards the metal pipe 114e, at which the inclined portion of junction face 116e is formed to have a recessed shape. Furthermore, the inner diameter at the vicinity of the junction face of the metal pipe junction may be made larger than the inner diameter at positions away from the junction face.
    Type: Grant
    Filed: May 17, 2001
    Date of Patent: July 15, 2003
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Takao Shimizu, Hirotsugu Horio, Kazushige Kito, Shigeyuki Inagaki, Ryuzo Yamada
  • Patent number: 6582833
    Abstract: A Ti-base wire rod for forming molten metal excellent both in rod feeding smoothness and arc stability is disclosed. A wire rod 301 is composed of Ti metal, and has in the surficial portion including the surface thereof an oxygen enriched layer having an oxygen concentration higher than that in an inner portion. Ratio Tw/Dw of the thickness Tw of the oxygen enriched layer and the diameter Dw of the wire rod is adjusted within a range of 1×10−3 to 1×10−1, and the average oxygen concentration of the oxygen enriched layer is adjusted to 1 wt % or above.
    Type: Grant
    Filed: July 11, 2002
    Date of Patent: June 24, 2003
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Kazuhiro Toyoda, Makoto Chujoya, Shigeo Hanajima, Takashi Suzuki, Takashi Orii, Takao Shimizu, Toshiharu Noda, Bunji Naito, Kohachiro Ohashi