Nippon Steel Sumitomo Metal Corporation

Nippon Steel Corporation

Kouichi Takeuchi

Hideya Kaminaka

Masayuki Shibuya

Satoshi Matsumoto

Kentarou Yoshida

Hayato Kita

Shinya Yamamoto

Hiroshi Kamio

Junko Imamura

Akira Seki

Masaru Abe

Hidenori Takebe

Atsuhiko Kuroda

Kazuyoshi Fujisawa

Shuuji Yoshida

Tomoyuki Sukawa

Shinnya Yamamoto

Katsuhiko Taketsu

Kentaroh Yoshida

Yoshihisa Yonemitsu

Norio Inoue

Daisaku Arizono

Syuji Yoshida

A titanium plate includes a chemical composition of industrial pure titanium, in which an arithmetic mean roughness Ra of a surface is 0.05 &#x3bc;m or more and 0.40 &#x3bc;m or less, the surface has titanium carbide regarding which a ratio between a total sum of integrated intensities Ic derived from the titanium carbide and a total sum of integrated intensities Im of all diffraction peaks derived from the titanium carbide and titanium obtained from X-ray diffractometry ((Ic/Im)&#xd7;100) is 0.8% or more and 5.0% or less, a number density of asperities on the surface is 30 to 100 pieces/mm, and an average spacing of the asperities is 20 &#x3bc;m or less.

Titanium plate

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 metal plate for laser processing (such as a stainless steel plate or a titanium plate) and preferably an austenitic stainless steel plate suitable for use as a metal mask or the like which undergoes fine processing with a laser has an average grain diameter d (&#x3bc;m) and a plate thickness t (&#x3bc;m) which satisfy the equation d&#x2264;0.0448&#xb7;t&#x2212;1.28.

Metal plate for laser processing and method for producing stainless steel plate for laser processing

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 high-Si content austenitic stainless steel, which exhibits stable acid resistance and excellent corrosion resistance in high-temperature and concentrated nitric acid, has a chemical composition comprising: C: at most 0.04%; Si: 2.5-7.0%; Mn: at most 10%; P at most 0.03%; S: at most 0.03%; N: at most 0.035%; sol. Al: at most 0.03%; Cr: 7-20%; Ni: 10-22%; optionally, one or more types selected from Nb, Ti, Ta and Zr: 0.05-0.7% in total; and the remainder being Fe and impurities, wherein a total amount of Btype inclusions measured by a method according to JIS G0555 (2003) Annex 1 'Microscopic Testing for the Non-Metallic Inclusions on the Point Counting Principle' is not more than 0.03% by area %.

Method for manufacturing high-Si austenitic stainless steel

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Tokyo, Japan

Kouichi Takeuchi