ISHIFUKU Metal Industry Co. | Date: 2015-06-23
An object of the present invention is to provide a molten ingot of a platinum group metal or a platinum group-based alloy having a high material yield by suppressing a scattering phenomenon during heating and melting in a method for producing a platinum group metal or a platinum group-based alloy. The method for producing a platinum group metal or a platinum group-based alloy according to the present invention includes a preparing step of weighing a raw material that is partially or entirely of powder and, when the alloy is to be produced, mixing the weighed raw material to obtain a powder mixture, a molding step of molding and solidifying the prepared raw material to obtain molded bodies, a sintering step of sintering the molded bodies to obtain a sintered body, a melting step of melting the sintered body to produce a molten ingot, and a deformation processing step of processing the molten ingot. In the sintering step, the molded bodies are sintered in a stacked state to produce a sintered body as a joined body.
ISHIFUKU Metal Industry Co. | Date: 2015-03-27
Provided is a method for producing a platinum group-based alloy capable of producing a sound molten ingot of a platinum group-based alloy in a large amount. The method for producing a platinum group-based alloy includes a molten ingot production step of a continuous casting system using a plasma arc melting furnace configured to form a plasma arc column between an electrode torch which is arranged in an upper part of a vacuum chamber and a water cooled copper crucible which is arranged in a lower part of the chamber and has a cavity having a sectional area S1, the molten ingot production step including: inserting and melting an end part of a raw material bar including a platinum group-based alloy in the plasma arc column to cause the raw material bar to fall in drops on a base material in the water cooled copper crucible, to thereby form a molten pool; and solidifying a bottom part of the molten pool while maintaining a constant liquid level height of the molten pool by pulling down the base material, the molten ingot having a horizontal sectional area S (mm^(2)) and a length L (mm) satisfying the following relationship: S1S>500, L>4(S/), an internal pressure of the chamber during melting being 0.8 atm or more, a pulling down speed of the base material being 10 mm/min or less.
Wang X.,Kyoto University |
Orikasa Y.,Kyoto University |
Takesue Y.,Chiba University |
Inoue H.,Ishifuku Metal Industry Ltd Company |
And 4 more authors.
Journal of the American Chemical Society | Year: 2013
Lattice strain of Pt-based catalysts reflecting d-band status is the decisive factor of their catalytic activity toward oxygen reduction reaction (ORR). For the newly arisen monolayer Pt system, however, no general strategy to isolate the lattice strain has been achieved due to the short-range ordering structure of monolayer Pt shells on different facets of core nanoparticles. Herein, based on the extended X-ray absorption fine structure of monolayer Pt atoms on various single crystal facets, we propose an effective methodology for evaluating the lattice strain of monolayer Pt shells on core nanoparticles. The quantitative lattice strain establishes a direct correlation to monolayer Pt shell ORR activity. © 2013 American Chemical Society.
Inoue H.,Gunma University |
Inoue H.,Ishifuku Metal Industry Co. |
Hosoya K.,Gunma University |
Kannari N.,Gunma University |
Ozaki J.-I.,Gunma University
Journal of Power Sources | Year: 2012
The influences of the heat-treatment of Ketjen Black EC300J in the temperature range 1000-2000 °C on the catalytic activity of loaded Pt for oxygen reduction reaction (ORR) were studied. A maximum enhancement in the specific ORR activities (SOA) was observed for the carbon heat-treatment at 1500 °C. The heat-treatment of carbon induced decreases in porosity and the development of graphitic structures; however, no direct correlations were observed between these properties and the SOA. Transmission electron microscopy and X-ray photoelectron spectroscopy, respectively, showed enhancements in the uniformity of the Pt particle size distribution and of the extent of surface reduction of Pt with increasing heat-treatment temperature (HTT). Cyclic voltammetry in 0.5 M H 2SO 4 aqueous solution detected changes in the hydrogen adsorption at 0.12 V vs. a reversible hydrogen electrode, depending on the HTT of the carbon support, and this was ascribed to hydrogen adsorption on the Pt(110) surface, the most active crystal face of Pt for ORR. The fraction of Pt atoms belonging to the (110) surface out of the total surface Pt atoms showed an excellent correlation with the SOA. Heat-treatment of the carbon support was therefore concluded to be an effective treatment for enhancing the SOA of Pt. © 2012 Elsevier B.V. All rights reserved.
Uemoto M.,Tokyo Institute of Technology |
Kobayashi T.,Japan National Institute of Materials Science |
Sasaki Y.,Ishifuku Metal Industry Co. |
Shimada K.,Ishifuku Metal Industry Co. |
And 4 more authors.
Analytical Methods | Year: 2011
A collaborative determination of the major components of silver brazing filler metals (Ag-Cu-Zn-Cd, Ag-Cu-Zn-Ni, and Ag-Cu-Zn-Sn alloys) by inductively coupled plasma atomic emission spectrometry (ICP-AES) was conducted. The classical wet methods of gravimetry and titrimetry were also investigated for comparison, most of which are provided by Japanese Industrial Standards (JIS). Results of instrumental and classical analyses using a simple dissolution procedure with nitric acid showed excellent trueness and precision amongst all laboratories and for all alloys except those containing tin. The tin-containing alloy had to be dissolved, suppressing precipitation of the sparingly soluble hydrous tin(iv) oxide. Dissolution with mixtures of nitric and sulfuric acid gave the most satisfactory results without precipitation, thus enabling an accurate determination that favourably compared to the classical wet results. Finally we have evaluated the ICP-AES method and a hybrid method with gravimetry and ICP-AES according to the precision required, and found them to be suitable for standardization. © 2011 The Royal Society of Chemistry.
Ishifuku Metal Industry Co. | Date: 2012-12-03
This invention provides sputtering target materials having high reflectance and excellent heat resistance, which are formed of Ag base alloys formed by adding a specific, minor amount of P to Ag and alloying them.
Ishifuku Metal Industry Co. and Denso Corporation | Date: 2013-08-19
A spark plug has a center electrode and an earth electrode. The center electrode is faced to the earth electrode so that a spark discharging gap is formed between the center electrode and the earth electrode. An electrode chip is formed on at least one of the center electrode and the earth electrode. The electrode chip has a composition comprised of 40 to 60 mol % of aluminum and iridium as a remainder thereof. In the composition of the electrode chip, it is possible to replace part of the iridium with 1 to 20 mol % of at least one metal selected from nickel, iron, cobalt, platinum and rhodium.
ISHIFUKU Metal Industry Co. and Denso Corporation | Date: 2013-09-30
A spark plug for use in an internal combustion engine has a center electrode, an earth electrode, and an electrode chip formed on at least one of the center electrode and the earth electrode. A spark discharge gap is formed between the center electrode and the earth electrode. The electrode chip has a base section, a chromium rich layer formed on at least a part of the base section, and a diffusion layer formed between the base section and the chromium rich layer. The base section contains chromium within a range of 5 to 45 mass %, an element X within a range of 0.5 to 25 mass %, and a remainder composed of tungsten and unavoidable impurity. The chromium rich layer is larger in content of chromium than the base section. The element X contained in the base section is comprised of at least one of molybdenum, silicon, aluminum and lead.