Patents by Inventor Takaji Takahashi

Takaji Takahashi 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: 5156690
    Abstract: A building low yield ratio hot-dip galvanized cold rolled steel sheet having an improved refractory property, consists essentially of, by weight, 0.1% or less of C, 0.1 to 1.5% of Mn, 0.1% of less of P, 0.06% or less of Al, 0.6 to 2.0% of Cu, and a remainder of Fe and unavoidable impurities and having a 0.6 times or more yield point strength at 600.degree. C. compared to that at normal temperatures. The method of forming the steel sheet comprises the steps of: forming a slab from a steel consisting essentially of, by weight, 0.1% or less of C, 0.1 to 1.5% of Mn, 0.1% or less of P, 0.06% or less of Al, 0.6 to 2.0% of Cu, and a remainder of Fe and unavoidable impurities, immediately or after heating the slab at a temperature of 1200.degree. C. or less, hot rolling the slab at a temperature of 750.degree. C. or more and cold rolling, effecting a continuous hot-dip galvanizing process, heating the rolled slab at a temperature of 700.degree. to 900.degree. C.
    Type: Grant
    Filed: November 21, 1990
    Date of Patent: October 20, 1992
    Assignee: Nippon Steel Corporation
    Inventors: Hirohide Asano, Kazuo Koyama, Takaji Takahashi, Nobuhiko Matsuzu