Patents by Inventor Robert A. Marra

Robert A. Marra 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: 6309994
    Abstract: A method of forming fiber reinforced aluminum phosphate bonded material having improved strength at elevated temperatures. The method comprises the steps of: (a) preparing a slurry by blending alumina and alumina phosphate solution, the slurry being substantially free of silica; (b) providing a fiber substrate; (c) infiltrating the solution into the fiber substrate; and (d) curing the infiltrated substrate to form a fiber reinforced aluminum phosphate bonded composite material. In a preferred embodiment of the present invention, the fiber substrate is made from SiC fibers.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: October 30, 2001
    Assignee: Aluminum Company of America
    Inventors: Robert A. Marra, Donald J. Bray, G. Edward Graddy, Jr., Siba P. Ray
  • Patent number: 5371050
    Abstract: A method of forming fiber reinforced aluminum phosphate bonded material having improved strength at elevated temperatures. The method comprises the steps of: (a) preparing a slurry by blending alumina and aluminum phosphate solution, the slurry being substantially free of silica; (b) providing a fiber substrate coated with a metal selected from the group consisting of nickel, tungsten, molybdenum, platinum, copper, silver, gold, palladium, cobalt, chromium and titanium; (c) infiltrating the slurry into the fiber substrate; and (d) curing the infiltrated substrate to form a fiber reinforced aluminum phosphate bonded composite material. In a preferred embodiment of the present invention, the fiber substrate is made from SiC fibers and the refractory metal is electrolessly coated nickel.
    Type: Grant
    Filed: April 4, 1991
    Date of Patent: December 6, 1994
    Assignee: Aluminum Company of America
    Inventors: David L. Belitskus, Daniel J. Boland, W. Thomas Evans, William P. Kampert, Robert A. Marra, Larry F. Wieserman
  • Patent number: 5194202
    Abstract: A method of forming a ceramic-metal composite including steps of providing a body of ceramic material; infiltrating molten metal into open spaces of the body at an elevated pressure; cooling the metal to form a solid composite; and reacting a portion of the metal in the composite at an elevated temperature with an oxidizing gas. A particularly preferred composite is made by infiltrating an alumina body with an aluminum alloy and then oxidizing in air at an elevated temperature. The composite is useful for making armor plate and other products where a combination of high hardness, good strength, and light weight are needed.
    Type: Grant
    Filed: September 12, 1991
    Date of Patent: March 16, 1993
    Assignee: Aluminum Company of America
    Inventors: David I. Yun, Robert A. Marra, Thomas B. Gurganus, P. Victor Kelsey, Jr.
  • Patent number: 4678657
    Abstract: The invention comprises a process for the production of high purity substantially spherical metal oxide particles using seed nuclei without introducing impurities into the desired product which comprises forming a metal alkoxide vapor; reacting the vapor with a non-reactive gas containing sufficient water vapor to hydrolyze a portion of the metal alkoxide vapor to form solid seed nuclei of metal hydroxide; cooling the remaining metal alkoxide vapor containing the metal hydroxide seed nuclei sufficiently to form an aerosol comprising finely divided metal alkoxide liquid condensed on the solid metal hydroxide seed nuclei; hydrolyzing the metal alkoxide aerosol by contact with water vapor to hydrolyze the metal alkoxide liquid to form substantially spherical metal hydroxide particles; and calcining the substantially spherical metal hydroxide particles to form the corresponding metal oxide.
    Type: Grant
    Filed: June 10, 1985
    Date of Patent: July 7, 1987
    Assignee: Aluminum Company of America
    Inventors: Ajay Sood, Robert A. Marra