Patents by Inventor Kikuo Takashina

Kikuo Takashina 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: 3990923
    Abstract: A method of producing a grain-oriented electromagnetic steel sheet comprising the step of subjecting a sheet of hot-rolled steel containing silicon less than 4.5% to more than one operation of cold rolling and more than one operation of annealing, so as to set the thickness of said sheet to that of a commercially standard sheet, and also subjecting the sheet to the step of final high-temperature annealing. Prior to said final high-temperature annealing, part of the surface of said sheet is worked for controlling the growth of secondary recrystallization grains by working the sheets such that lines of less than 3.0 mm wide are formed on the surface of the steel sheet spaced apart at intervals of more than 5.0 mm so that the total effect is to produce worked and unworked regions alternatively arranged in lines across the steel sheet. Such working is effected by mechanical plastic working, local thermal treatment and by chemical treatment.
    Type: Grant
    Filed: April 24, 1975
    Date of Patent: November 9, 1976
    Assignee: Nippon Steel Corporation
    Inventors: Kikuo Takashina, Yozo Suga, Masahiro Fukumoto, Takaaki Yamamoto, Osamu Tanaka, Katsuro Kuroki
  • Patent number: 3941623
    Abstract: Method for producing a grain-oriented electrical steel sheet or strip having uniform magnetic and film properties said method comprising applying an annealing separator containing one or more metal nitrides, such as, chromium nitride, titanium nitride and vanadium nitride to the steel sheet and annealing the steel sheet at a temperature not lower than 1,100.degree.C.
    Type: Grant
    Filed: August 23, 1974
    Date of Patent: March 2, 1976
    Assignee: Nippon Steel Corporation
    Inventors: Kikuo Takashina, Minoru Kitayama, Motoharu Nakamura, Yozo Suga, Kiyoshi Tanaka