Patents by Inventor John V. Milewski

John V. Milewski 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: 5404836
    Abstract: Described herein is a method and apparatus for continuously growing single crystal whiskers of silicon carbide, silicon nitride, boron carbide and boron nitride by the VLS process under controlled reaction conditions. A growth substrate such as a plate of solid graphite is coated with a suitable VLS catalyst and is conveyed through a tubular furnace, into which is separately introduced two feed gases. The first feed gas contains a cationic suboxide precursor such as silicon monoxide or boron monoxide. The second feed gas contains an anionic precursor compound such as methane or ammonia. The precursor compounds react upon exposure to the catalyst by the VLS process to produce crystalline whiskers. The associated apparatus includes a conveyor assembly that continuously circulates multiple substrate growth plates through the furnace and past a harvesting device which brushes the whiskers from the plates and removes them by vacuum collection. Whiskers of uniform size, shape, and purity are produced.
    Type: Grant
    Filed: November 9, 1989
    Date of Patent: April 11, 1995
    Inventor: John V. Milewski
  • Patent number: 4864186
    Abstract: An electric light filament comprising a single crystal whisker is disclosed. In the preferred embodiment the whisker consists essentially of silicon carbide (SiC), preferably beta silicon carbide, doped with a sufficient amount of nitrogen to render the whisker sufficiently electrically conductive to be useful as a light bulb filament at household voltages. Filaments made of such materials are characterized by high strength, durability, and resilience, and have higher electrical emissivities than conventioanl tungsten filaments.
    Type: Grant
    Filed: March 29, 1988
    Date of Patent: September 5, 1989
    Inventors: John V. Milewski, Peter D. Milewski
  • Patent number: 4513030
    Abstract: A method of producing articles comprising reaction-bonded silicon carbide (SiC) and graphite (and/or carbon) is given. The process converts the graphite (and/or carbon) in situ to SiC, thus providing the capability of economically obtaining articles made up wholly or partially of SiC having any size and shape in which graphite (and/or carbon) can be found or made. When the produced articles are made of an inner graphite (and/or carbon) substrate to which SiC is reaction bonded, these articles distinguish SiC-coated graphite articles found in the prior art by the feature of a strong bond having a gradual (as opposed to a sharply defined) interface which extends over a distance of mils. A method for forming SiC whisker-reinforced ceramic matrices is also given. The whisker-reinforced articles comprise SiC whiskers which substantially retain their structural integrity.
    Type: Grant
    Filed: June 18, 1982
    Date of Patent: April 23, 1985
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: John V. Milewski
  • Patent number: 4214920
    Abstract: The present invention relates to the production of high purity solar grade silicon from common rice hulls. A unique process for material purification and reduction includes leaching the rice hulls in acid followed by treatment with high purity water, coking the acid-cleaned hulls in a non-oxidizing ambient, compensating the carbon or silica content of the coked hulls to obtain a desired carbon to silica ratio and reducing the silica to produce high purity silicon.
    Type: Grant
    Filed: March 23, 1979
    Date of Patent: July 29, 1980
    Assignee: Exxon Research & Engineering Co.
    Inventors: James A. Amick, John V. Milewski, Franklin J. Wright
  • Patent number: 4083708
    Abstract: Adherent layers of glass are deposited on a preform or substrate via the controlled oxidation of a glass precursor, such as silicon monoxide, in the vapor state, thereby providing unusual shaped composite articles having a glass coating on the substrate. A preform or substrate such as carbon can subsequently be oxidized, thereby providing a glass microcapillary of exceedingly uniform dimensions.
    Type: Grant
    Filed: July 13, 1977
    Date of Patent: April 11, 1978
    Assignee: Exxon Research & Engineering Co.
    Inventors: Carl E. Heath, Daniel Grafstein, John V. Milewski