Patents by Inventor Nakatsugu Abe

Nakatsugu Abe 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).

  • Patent number: 5116571
    Abstract: A chromium heat-resistant steel excellent in toughness and having a high cracking resistance and a high creep strength when said steel is utilized to form a welded joint, said steel consisting essentially of:______________________________________ carbon: from 0.04 to 0.09 wt. %, silicon: from 0.01 to 0.50 wt. %, manganese: from 0.25 to 1.50 wt. %, chromium: from 7.0 to 9.2 wt. %, molybdenum: from 0.50 to 1.50 wt. %, soluble aluminum: from 0.005 to 0.060 wt. %, nitrogen: from 0.001 to 0.060 wt. %, ______________________________________where, the total amount of nitrogen and carbon being up to 0.13 wt. %, at least one element selected from the group consisting of: ______________________________________ vanadium: from 0.01 to 0.30 wt. %, and niobium: from 0.005 to 0.200 wt. %, ______________________________________where, the total amount of vanadium and 1.5 times niobium being up to 0.30 wt. %, and the balance being iron and incidental impurities; and the amount of ferrite as represented by the ferrite number (.
    Type: Grant
    Filed: July 12, 1991
    Date of Patent: May 26, 1992
    Assignee: Nippon Kokan Kabushiki Kaisha
    Inventors: Nakatsugu Abe, Haruo Suzuki, Hiroaki Tsukamoto, Seishi Tsuyama, Moriyasu Nagae