Patents by Inventor Carol J. Willman

Carol J. Willman 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).

  • Patent number: 4994109
    Abstract: A method for producing permanent magnet alloy particles suitable for use in producing bonded permanent magnets. A melt or molten mass of a permanent magnet alloy having at least one rare earth element, at least one transition element, preferably iron, and boron is produced. The melt is inert gas atomized to form spherical particles within the size range of 1 to 1000 microns. The particles are heat treated in a nonoxidizing atmosphere for a time at temperature to significantly increase the intrinsic coercivity of the particles without sintering the particles to substantially full density. Thereafter, the particles are separated to produce a discrete particle mass. The particles during heat treatment may be maintained in motion to prevent sintering thereof.
    Type: Grant
    Filed: May 5, 1989
    Date of Patent: February 19, 1991
    Assignee: Crucible Materials Corporation
    Inventors: Carol J. Willman, Edward J. Dulis, Francis S. Snyder
  • Patent number: 4588439
    Abstract: A permanent magnet alloy that when used in the production of a permanent magnet results in a magnet that is highly resistant to disintegration when exposed to a combination of humidity and heat. Consequently, the alloy consists essentially of, in weight percent, 30 to 36 of at least one rare earth element, 60 to 66 iron, 6,000 to 35,000 ppm oxygen and balance boron.
    Type: Grant
    Filed: May 20, 1985
    Date of Patent: May 13, 1986
    Assignee: Crucible Materials Corporation
    Inventors: Kalathur S. V. L. Narasimhan, Carol J. Willman, Edward J. Dulis