Patents by Inventor Koichi Hanawa

Koichi Hanawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230287560
    Abstract: A method for producing a chromium sintered body includes a heat treatment step of heat-treating electrolytic chromium flakes at 1,200° C. or higher and 1,400° C. or lower, and a firing step of, after the heat treatment step, filling a container with the electrolytic chromium flakes and firing a resulting filling product by hot isostatic pressing.
    Type: Application
    Filed: March 8, 2023
    Publication date: September 14, 2023
    Inventors: Masami MESUDA, Daiki SHONO, Kenichi ITOH, Koichi HANAWA
  • Patent number: 5236661
    Abstract: A chromium weld material comprising chromium as a main component and either one of or an appropriate combination of elements selected from the group IVb metals of the periodic table, Al, metals belonging to the groups VIIb, VIII, and Ib of the periodic table, Nb, and Ta and, if desired, at least one of rare earth elements, a chromium rolled article comprising chromium as a main component and either one of or an appropriate combination of elements selected from Al, Ti, Zr, Hf, Y, rare earth elements, and elements belonging to the groups Vb, VIb, and VIIb of the periodic table, and a process for producing said rolled article by cross-rolling under specific temperature and output rate conditions are disclosed. The weld material provides a weld free from deterioration of mechanical characteristics. The rolled article exhibits excellent tensile characteristics. The process provides a rolled sheet of small thickness without causing craking.
    Type: Grant
    Filed: February 11, 1992
    Date of Patent: August 17, 1993
    Assignee: Tosoh Corporation
    Inventors: Hiroaki Hidaka, Tsutomu Kuniya, Koichi Hanawa, Tomoyuki Oikawa
  • Patent number: 5154796
    Abstract: The present invention relates to giant grains or single crystals of chromium. Hitherto, since single crystals of chromium were generally obtained by a floating zone method, it was difficult to obtain an optionally shaped chromium single crystal. The present invention has been made in order to overcome these problems and provides a process for producing single crystals of chromium by secondary recrystallization. That is, it has been found that control of the amount of impurities present in a chromium component such as, for example, Co, Ti, Al, Si, and Ca, has a good influence on the formation of single crystals of chromium. For example, if chromium to which the above-described Ti, Al, Si, and Ca have been added in an amount of from 0.0002 wt % to 0.1 wt %, calculated as oxides thereof, or to which from 0.01 to 3 wt % of Co has further been added, is sintered and the resulting chromium molding is heated treated, single crystals of chromium having a complicated shape can be obtained.
    Type: Grant
    Filed: May 24, 1991
    Date of Patent: October 13, 1992
    Assignee: Tosoh Corporation
    Inventors: Tsutomu Kuniya, Koichi Hanawa, Hiroshi Tanaka, Shinji Sekine
  • Patent number: 5126106
    Abstract: A chromium weld material comprising chromium as a main component and either one of or an appropriate combination of elements selected from the group IVb metals of the periodic table, Al, metals belonging to the groups VIIb, VIII, and Ib of the periodic table, Nb, and Ta and, if desired, at least one of rare earth elements, a chromium rolled article comprising chromium as a main component and either one of or an appropriate combination of elements selected from Al, Ti, Zr, Hf, Y, rare earth elements, and elements belonging to the groups Vb, VIb, and VIIb of the periodic table, and a process for producing said rolled article by cross-rolling under specific temperature and output rate conditions are disclosed. The weld material provides a weld free from deterioration of mechanical characteristics. The rolled article exhibits excellent tensile characteristics. The process provides a rolled sheet of small thickness without causing craking.
    Type: Grant
    Filed: May 22, 1990
    Date of Patent: June 30, 1992
    Assignee: Tosoh Corporation
    Inventors: Hiroaki Hidaka, Tsutomu Kuniya, Koichi Hanawa, Tomoyuki Oikawa
  • Patent number: 4917722
    Abstract: A method for producing a single crystal of chromium is disclosed, comprising sintering a chromium molding to thereby apply thereto a thermal strain and heat treating the resulting thermally strained chromium molding. The method achieves high efficiency of crystal growth and produces a single-crystal chromium molding of complicated shape.
    Type: Grant
    Filed: May 18, 1989
    Date of Patent: April 17, 1990
    Assignee: Tosoh Corporation
    Inventors: Tsutomu Kuniya, Koichi Hanawa, Tomoyuki Oikawa