Patents by Inventor Yasuyuki Tanno

Yasuyuki Tanno 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).

  • Galvannealed steel sheet and manufacturing method thereof
    Patent number: 5897967
    Abstract: A galvannealed steel sheet suited for use in automobiles, and a manufacturing method thereof. The steel sheet has tensile strength of 340 MPa or higher and paint bake hardenability of 10 MPa or higher, and excellent resistance to powdering when press formed, and excellent resistance to chipping in cold regions. The base metal of the galvannealed steel sheet consists essentially of C: 0.004-0.008%, Si: 2.5.times.P (%)-0.20%, Mn: 0.10-0.40%, P: 0.017-0.045%, sol. Al: 0.003-0.08%, Ti: 0.002-0.015%, Nb: 0.010-0.030 %, wherein Ti (%)+Nb (%): 0.012-0.035%. A steel sheet of the chemical composition described above is hot-dip galvanized, heated up to a Fe--Zn alloying temperature at a heating velocity of 20.degree. C./sec or higher, and upon completion of the Fe--Zn alloying process, cooled down from the Fe--Zn alloying temperature at a cooling velocity of 10.degree. C./sec or higher.
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: April 27, 1999
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Masahiko Hori, Toshio Nakamori, Yoshiaki Nakazawa, Yasuyuki Tanno