Patents by Inventor Frank S. Greenwald

Frank S. Greenwald 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).

  • Rare earth anisotropic magnetic materials for polymer bonded magnets
    Patent number: 5470400
    Abstract: This invention relates to a process for producing a non-pyrophoric, corrosion resistant rare earth-containing material capable of being formed into a polymer bonded permanent magnet comprising forming particles from a rare earth-containing alloy, and treating the alloy with a passivating gas comprised of nitrogen, carbon dioxide or a combination of nitrogen and carbon dioxide at a temperature below the phase transformation temperature of the alloy, and heat treating the alloy to produce material having a coercivity of at least 1,000 Oersteds. Rare earth-containing alloys suitable for use in producing magnets, such as Nd--Fe--B and Sm--Co alloys, can be used. If nitrogen is used as the passivating gas, the resultant powder particles have a nitrogen surface concentration of from about 0.4 to about 26.8 atomic percent. Moreover, if carbon dioxide is used as the passivating gas, the resultant powder particles have a carbon surface concentration of from about 0.02 to about 15 atomic percent.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: November 28, 1995
    Assignee: SPS Technologies, Inc.
    Inventors: Yakov Bogatin, Mark Robinson, Frank S. Greenwald, John Ormerod
  • Process for producing permanent magnets
    Patent number: 4911882
    Abstract: The present invention relates to the preparation of permanent magnet materials of the Iron-Boron-Rare Earth type.
    Type: Grant
    Filed: February 8, 1989
    Date of Patent: March 27, 1990
    Assignee: SPS Technologies, Inc.
    Inventor: Frank S. Greenwald