Patents Represented by Law Firm 30
  • Method for producing a grain-oriented electrical steel sheet having an ultra low watt loss
    Patent number: 4846939
    Abstract: The heat resistant subdivision of magnetic domains of a grain-oriented electrical steel sheet for improving the watt loss characterized by forming intruders therein is improved by pickling the steel sheet prior to the electroplating of the intrudable means. The partly exposed steel sheets are pickled by HNO.sub.3, H.sub.2 SO.sub.4 containing Fe.sup.3+, HCl containing Fe.sup.3+, and/or HBF.sub.4.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: July 11, 1989
    Assignee: Nippon Steel Corporation
    Inventors: Makoto Yoshida, Seijun Higuchi, Teruaki Izaki, Osamu Tanaka