Patents by Inventor Chris Chatfield

Chris Chatfield 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).

  • Sintering tray
    Patent number: 5993970
    Abstract: The present invention discloses a method of sintering of cemented carbide or cermet bodies lying on graphite trays. By using graphite trays coated with a covering layer of Y.sub.2 O.sub.3 containing .ltoreq.20 wt-% ZrO.sub.2, or corresponding volumetric amount of other refractory oxides, e.g., Al.sub.2 O.sub.3 or combinations thereof, with an average thickness of .gtoreq.10 .mu.m, the life of the trays between regrindings and recoatings can be largely extended.
    Type: Grant
    Filed: April 14, 1997
    Date of Patent: November 30, 1999
    Assignee: Sandvik AB
    Inventors: Ulf Oscarsson, Per Gustafson, Chris Chatfield, Mikael Lagerquist