Nippon Steel Sumitomo Metal Corporation

Nippon Steel Corporation

Nippon Steel Stainless Steel Corporation

Junko Imamura

Hideya Kaminaka

Yoshitaka Nishiyama

Masanari Kimoto

Kazuhiro Takahashi

Jun Maki

Koichi Nose

Kiyonori Tokuno

Yasuhiro Masaki

Taku Kagawa

Atsuhiko Kuroda

Yasuto Higashida

Kouichi Takeuchi

Akira Seki

Shunsuke Taniguchi

Junichi Higuchi

Shuuji Yoshida

Yoshiaki Yamade

Haruka Sato

Kohei Maejima

Yuya Takashima

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

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

In a titanium material or a titanium alloy material, in an oxide film formed on a surface of a titanium or a titanium alloy, the composition ratio of TiO (I/(I+I)&#xd7;100 found from the maximum intensity of the X-ray diffraction peaks of TiO (I) and the maximum intensity of the X-ray diffraction peaks of metal titanium (I) in X-ray diffraction measured at an incident angle to the surface of 0.3&#xb0; is 0.5% or more. A titanium material or a titanium alloy material, and a fuel cell separator and a polymer electrolyte fuel cell having good contact-to-carbon electrical conductivity and good durability can be provided.

Titanium material or titanium alloy material having surface electrical conductivity and method for producing the same, and fuel cell separator and fuel cell using the same

Provided is a metallic material including: a base metal made of a metal; a metal compound layer stacked on a surface of the base metal, the metal compound layer mainly containing a compound of at least one transition metal in the fourth period and oxygen; a platinum group portion dispersed on a surface of the metal compound layer, the platinum group portion mainly containing at least one platinum group element; and a platinum group compound coating film which covers the platinum group portion, the platinum group compound coating film mainly containing a compound of at least one platinum group element and oxygen. The at least one platinum group element contained in the platinum group portion is preferably one or more of Ru, Rh, Os, and Ir.

Metallic material, and conductive component including the same

The composition ratio of a titanium hydride [I/(I+I)]&#xd7;100 found from the maximum intensity of metal titanium (I) and the maximum intensity of the titanium hydride (I) of the X-ray diffraction peaks measured at a surface of a titanium or a titanium alloy at an incident angle to the surface of 0.3&#xb0; is 55% or more, a titanium oxide film is formed on an outermost surface of the titanium or the titanium alloy, and C is at 10 atomic % or less, N is at 1 atomic % or less, and B is at 1 atomic % or less in a position where the surface has been subjected to sputtering of 5 nm with argon. The titanium oxide film is formed by performing stabilization treatment after performing passivation treatment in prescribed aqueous solutions, and has a thickness of 3 to 10 nm.

Titanium material or titanium alloy material having surface electrical conductivity, and fuel cell separator and 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.

Growing community of inventors

Tokyo, Japan

Junko Imamura