Patents by Inventor Kazumi Asahi

Kazumi Asahi 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: 4863679
    Abstract: Disclosed are a cladding tube for a nuclear fuel and a nuclear fuel element incorporating the cladding tube. The cladding tube consists of an inner zirconium liner layer and an outer zirconium alloy layer. The cladding tube has at least one of the following features: (I) the ratio a/b of the oxygen content a to iron content b in the zirconium liner layer is greater than 1.0, (II) the zirconium liner layer is made of a zirconium into the matrix of which impurities are dissolved, and (III) the second phase particles having microscopic sizes and dispersed in the inner surface of the zirconium liner layer and/or the outer surface of the zirconium alloy layer have been removed substantially. Owing to these features, undesirable stress corrosion cracking and local corrosion are remarkably suppressed in the cladding tube and the nuclear fuel element of the invention.
    Type: Grant
    Filed: June 12, 1987
    Date of Patent: September 5, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Hiromichi Imahashi, Toshio Kubo, Kazumi Asahi, Hideyuki Mukai, Keizo Ogata