Nippon Steel & Sumitomo Metal Corporation

Nippon Steel Corporation

Sony Corporation

Other

Matsushita Electric Industrial Co., Ltd.

Sumitomo Metal Industries, Inc.

Nippon Steel Stainless Steel Corporation

Hideya Kaminaka

Noriyuki Negi

Junko Imamura

Masaru Abe

Kouichi Takeuchi

Kazuhito Kamei

Koji Moriguchi

Atsuo Omaru

Masayuki Nagamine

Yoshitaka Nishiyama

Mitsuhara Yonemura

Jun Maki

Harunari Shimamura

Satoshi Matsumoto

Koichi Nose

Yoshiaki Nitta

Kazuhiro Okamura

Kentarou Yoshida

Kazuhiro Takahashi

Shinya Yamamoto

Junichi Higuchi

Hiroshi Kamio

Yasuto Higashida

Mitsuharu Yonemura

Yasuhiro Masaki

Koji Akioka

Akira Seki

Masayuki Shibuya

Shunsuke Taniguchi

Hayato Kita

Eiji Ikeda

Shuuji Yoshida

Yoshiaki Yamade

Kohei Maejima

Yuya Takashima

Syuji Yoshida

Daisaku Arizono

Yoshihisa Yonemitsu

Norio Inoue

Haruka Sato

A coated titanium material includes a titanium material and a coating film formed on a surface of the titanium material. A Ti-based oxide is included in an interface between the titanium material and the coating film. The Ti-based oxide is one or both rutile type TiOand TiO. In a case where a cut surface of the coating film is formed by using a SAICAS method under conditions that a horizontal speed is 2 μm/s and a vertical speed is 0.1 μm/s, on the cut surface, an area percentage of the Ti-based oxide is 30.0% or more in a region having a distance of 15 μm from a reference line specified on the basis of a boundary line, which is an intersection line between the cut surface and the interface, to a coating film side.

Titanium material and coated titanium material

A titanium material including a base metal made of pure titanium or a titanium alloy and a titanium oxide film formed on the base metal. Peak intensities obtained by thin-film X-ray diffraction analysis performed on an outer layer of the titanium material using an incident angle of 0.3&#xb0; satisfy (I(104)+I(200))/I(101)&#x2265;0.08&#x2212;0.004&#xd7;I(200), where I(104) is the peak intensity resulting from a plane (104) of a TiOphase, I(200) is the peak intensity resulting from a plane (200) of a TiO phase, I(101) is the peak intensity resulting from a plane (101) of an &#x3b1;-Ti phase, and 0&#x3c;I(104), 0&#x2264;I(200), and 0&#x3c;I(101). The titanium material is inexpensive and has both the electrical conductivity and corrosion resistance.

Titanium material, separator, cell, and polymer electrolyte fuel cell stack

Provided are a stainless steel sheet with good corrosion resistance, low contact resistance and good press workability without the use of expensive materials such as gold or rare metals, and a method of manufacture the same. A method of manufacturing a stainless steel sheet includes: preparing a slab having a chemical composition including, in mass %: 20 to 26% Cr, up to 0.1% N, up to 2.0% Si, etc. (step S); performing hot rolling and cold rolling on the slab to produce a rolled steel sheet with a thickness of 50 to 200 &#x3bc;m (step S); an annealing step in which the rolled steel sheet is annealed and cooled in a gas atmosphere containing nitrogen (step S); and pickling the rolled steel sheet after the annealing step with a solution containing a non-oxidizing acid (step S). The stainless steel sheet has an N content of 0.6 to 2.0% by mass.

Stainless steel sheet and method of manufacturing the same, separator for solid polymer fuel cell, solid polymer fuel cell, and solid polymer fuel cell battery

Provided is a stainless steel product having a chemical composition consisting of C: less than 0.05%, Si: 4.0 to 7.0%, Mn: 1.50% or less, P: 0.030% or less, S: 0.030% or less, Cr: 10.0 to 20.0%, Ni: 11.0 to 17.0%, Cu: 0.15 to 1.5%, Mo: 0.15 to 1.5%, Nb: 0.5 to 1.2%, Sol. Al: 0 to 0.10%, Mg: 0 to 0.01%, and balance Fe and impurities, wherein MgO.AlOinclusions constitute an area fraction of 0.02% or less. This stainless steel product has excellent corrosion resistance to hot concentrated sulfuric acid of approximately 93 to 99% concentration, for example, and also is economically advantageous.

Stainless steel product

A titanium product for a separator of a proton exchange membrane fuel cell according to the present invention includes: a base material that consists of commercially pure titanium; a first oxide layer that is formed in a surface layer of the titanium product, consists of TiOof a rutile crystallinity, and has a thickness of 0.1 to 1.5 nm; and a second oxide layer that is formed between the base material and the first oxide layer, consists of TiO(1&#x3c;x&#x3c;2), and has a thickness of 3 to 20 nm. This titanium product is suitable to be used as a separator of a proton exchange membrane fuel cell that has a high corrosion resistance in an environment in a fuel cell, is capable of keeping a low contact resistance with an electrode consisting of carbon fiber and the like, and is inexpensive.

Titanium product, separator, and proton exchange membrane fuel cell, and method for producing titanium product

A titanium alloy including by mass %, a platinum group metal: 0.01 to 0.15% and a rare earth metal: 0.001 to 0.10%, with the balance being Ti and impurities. The titanium alloy preferably includes as a partial replacement for Ti, Co: 0.05 to 1.00% by mass, and the content of the platinum group metal is preferably in the range of 0.01 to 0.05% by mass. Furthermore, it is preferred that the platinum group metal be Pd and the rare earth metal be Y. Consequently, it is possible to provide a titanium alloy having corrosion resistance comparable to or better than that of the conventional art as well as good workability while offering an economic advantage with a lower content of platinum group metal or an advantage of less likelihood of corrosion growth originating at defects such as flaws that occurred in the surface.

Titanium alloy

The clad material comprises outer layers each consisting of Ni or Ni alloy and a base layer consisting of Cu or Cu alloy, and is characterized in that peeling-off at a clad boundary is not recognized in cross section observation made after the clad material has been subjected to a 90&#xb0; reverse bend test ten times, and the number of reverse bend cycles before rupture is 17 cycles or more. The clad material has with both of excellent corrosion resistance against electrolytic solution and high electric conductivity.

Clad material

A titanium material for a polymer electrolyte fuel cell separator consists of, by mass %, a platinum group metal: 0.005% to 0.15% and a rare earth metal: 0.002% to 0.10%, with the balance being Ti and impurities. The titanium material of the present invention is provided with a film formed of a titanium oxide and a platinum group metal on the surface thereof. It is preferred that the film has a thickness of 50 nm or less, and that the concentration of the platinum group metal on the surface of the film is 1.5% by mass or more. With the thus formed film, the titanium material of the present invention is capable of achieving a reduction in initial contact resistance and ensuring good corrosion resistance. In the titanium material of the present invention, the rare earth metal is preferably Y, and the platinum group metal is preferably Pd.

Titanium material for polymer electrolyte fuel cell separator, method for producing the same, and polymer electrolyte fuel cell using the same

A stainless steel member for a separator of a solid polymer fuel cell has excellent cell properties with little deterioration in performance over long periods of operation without worsening of the corrosion resistance of a stainless steel separator. The stainless steel member has a stainless steel base metal, and a passive film and electrically conductive precipitates both provided on a surface of the stainless steel base metal. The electrically conductive precipitate penetrates the passive film and includes a substance originating from the stainless steel base metal. An electrically conductive layer comprising a nonmetallic electrically conductive substance is preferably provided on the surface of the passive film, and the electrically conductive layer is preferably electrically connected to the stainless steel base member through the electrically conductive precipitates.

Stainless steel sheet for a separator for a solid polymer fuel cell and a solid polymer fuel cell employing the separator

A stainless steel member comprising a stainless steel base metal; an oxide film located on the surface of the stainless steel base metal; an electroconductive layer located on the surface of the oxide film and comprising a nonmetallic electroconductive material; and an electroconductive material which is located so as to penetrate the oxide film and which electrically contacts the stainless steel base metal and the electroconductive layer is provided as a stainless steel member for a separator of a solid polymer fuel cell having excellent properties such that a degradation in performance is low even after prolonged operation. A solid polymer fuel cell using the stainless steel member is also provided.

Stainless steel material for a separator of a solid polymer fuel cell and a solid polymer fuel cell using the separator

The present invention provides a duplex stainless steel having excellent resistance to alkalis and particularly corrosion resistance against high-temperature concentrated alkali solutions and excellent weldability. The duplex stainless steel has a chemical composition comprising, in mass %, C: at most 0.03%, Si: at most 0.5%, Mn: at most 2.0%, P: at most 0.04%, S: at most 0.003%, Cr: at least 25.0% to less than 28.0%, Ni: at least 6.0% to at most 10.0%, Mo: at least 0.2% to at most 3.5%, N: less than 0.5%, W: at most 3.0%, and a remainder of Fe and impurities.

Duplex stainless steel having excellent alkali resistance

A graphite powder suitable for a negative electrode material of a lithium ion secondary battery which assures a high discharging capacity not lower than 320 mAh/g is to be manufactured at a lower cost. Specifically, a graphite powder containing 0.01 to 5.0 wt % of boron and having a looped closure structure at an end of a graphite c-planar layer on the surface of a powder, with the density of the interstitial planar sections between neighboring closure structures being not less than 100/&#x3bc;m and not more than 1500/&#x3bc;m, and with dbeing preferably not larger than 3.3650 &#x212b;, is manufactured by (1) heat-treating a carbon material pulverized at an elevated speed before or after carbonization for graphization at temperature exceeding 1500&#xb0; C. or by (2) heat-treating the carbon material pulverized before or after carbonization at a temperature exceeding 1500&#xb0; C. for graphization and subsequently further heat-treating the graphized material at a temperature exceeding a temperature of the oxidating heat treatment and the heat treatment in the inert gas.

Graphite powders suited for negative electrode material of lithium ion secondary battery

A graphite powder suitable for a negative electrode material of a lithium ion secondary battery which assures a high discharging capacity not lower than 320 mAh/g is to be manufactured at a lower cost. Specifically, a graphite powder containing 0.01 to 5.0 wt % of boron and having a looped closure structure at an end of a graphite c-planar layer on the surface of a powder, with the density of the interstitial planar sections between neighboring closure structures being not less than 100/&#x3bc;m and not more than 1500/&#x3bc;m, and with dbeing preferably not larger than 3.3650 &#x212b;, is manufactured by (1) heat-treating a carbon material pulverized at an elevated speed before or after carbonization for graphization at temperature exceeding 1500&#xb0; C. or by (2) heat-treating the carbon material pulverized before or after carbonization at a temperature exceeding 1500&#xb0; C. forgraphization and subsequently further heat-treating the graphized material at a temperature exceeding a temperature of the oxidating heat treatment and the heat treatment in the inert gas.

A negative electrode material for a nonaqueous electrolyte secondary battery having a high discharge capacity and a good cycle life is made from alloy particles having an average particle diameter of 0.1-50 &#x3bc;m and including Si phase grainsand a phase of a solid solution or an intermetallic compound of Si and other element selected from Group 2A elements, transition elements, Group 3B elements, and Group 4B elements from the long form periodic table (for example, an NiSiphaseand an [NiSi+NiSi] phase) at least partially enveloping the Si phase grains. 5-99 wt % of this material is Si phase grains. The alloy particles can be manufactured by rapid solidification (such as atomization or roller quenching) of a melt including Si and the other element, or by adhering the other element to Si powder by electroless plating or mechanical alloying and then performing heat treatment. Even if rapid solidification is carried out, a negative electrode material having a good discharge capacity and cycle life is obtained without heat treatment.

Process for manufacture of negative electrode material for a non-aqueous electrolyte secondary battery

A negative electrode material for a nonaqueous electrolyte secondary battery having a high discharge capacity and a good cycle life is made from alloy particles having an average particle diameter of 0.1-50 &mgr;m and including Si phase grains 40 and a phase of a solid solution or an intermetallic compound of Si and other element selected from Group 2A elements, transition elements, Group 3B elements, and Group 4B elements from the long form periodic table (for example, an NiSi phase 42 and an &lsqb;NiSi &plus;NiSi&rsqb; phase 41) at least partially enveloping the Si phase grains. 5-99 wt % of this material is Si phase grains. The alloy particles can be manufactured by rapid solidification (such as atomization or roller quenching) of a melt including Si and the other element, or by adhering the other element to Si powder by electroless plating or mechanical alloying and then performing heat treatment. Even if rapid solidification is carried out, a negative electrode material having a good discharge capacity and cycle life is obtained without heat treatment.

Negative electrode material for a non-aqueous electrolyte secondary battery and processes for its manufacture

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Tokyo, Japan

Hideya Kaminaka