Patents by Inventor Erik T. Hartzell

Erik T. Hartzell 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).

  • Cemented carbide body with a binder phase gradient and method of making the same
    Patent number: 4820482
    Abstract: The present invention relates to a cemented carbide body, preferably for rock drilling, mineral cutting and wear parts, in which the content of binder phase in the surface is lower and in the center higher than the nominal content. In the center there is a zone having a uniform content of binder phase. The WC grain size is uniform throughout the body.
    Type: Grant
    Filed: May 5, 1987
    Date of Patent: April 11, 1989
    Assignee: Santrade Limited
    Inventors: Udo K. R. Fischer, Erik T. Hartzell, Jan G. H. Akerman
  • Cemented carbide tool
    Patent number: 4764255
    Abstract: A tool or wear part comprises a cast iron or cast steel body carrying a plurality of cast-in inserts. Each insert comprises a cemented carbide cutting or wearing element partially embedded in the body, and an enclosure completely surrounding the embedded portion of the element. The enclosure is cast-in with respect to the body and has a higher melting point than the body. The enclosure is connected by a metallurgical bond to the body and by a shrink-fit to the element.
    Type: Grant
    Filed: March 13, 1987
    Date of Patent: August 16, 1988
    Assignee: Sandvik AB
    Inventors: Udo K. R. Fischer, Erik T. Hartzell, Mats G. Waldenstrom
  • Cemented carbide body used preferably for rock drilling and mineral cutting
    Patent number: 4743515
    Abstract: The present invention relates to cemented carbide bodies preferably for rock drilling and mineral cutting. By having the bodies comprising a core of cemented carbide containing eta-phase surrounded by a surface zone of cemented carbide free of eta-phase and having a low content of cobalt in the surface and a higher content of cobalt next to the eta-phase zone the bodies have obtained an increased strength and life in practical use.
    Type: Grant
    Filed: October 25, 1985
    Date of Patent: May 10, 1988
    Assignee: Santrade Limited
    Inventors: Udo K. R. Fischer, Erik T. Hartzell, Jan G. H. Akerman