Patents by Inventor Takashi Kikuhara

Takashi Kikuhara 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: 5081760
    Abstract: A compound roll for a metal rolling mill having both excellent resistance to a thermal shock crack and excellent wear resistance includes a core shaft made of low alloy steel and an outer layer consisting of high speed tool steel having a composition, by weight percent, essentially of 0.5 to 1.5% of C, 0.5 to 3.0% of Si, 1.5% or less of Mn, 2 to 7% of Cr, 1 to 5% of Mo, 0.5 to 2.0% of V, up to 2.0% of W and balance essentially Fe. The outer layer is formed on the outer surface of the core shaft by an electro-slag method. The outer layer is subjected to a water jet spray quenching and tempering at 300.degree. C. or higher, preferably 450.degree. C. to 550.degree. C.
    Type: Grant
    Filed: June 20, 1990
    Date of Patent: January 21, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Kikuhara, Osamu Shitamura, Yasuo Kondo