Patents by Inventor Pradeep Kumar Rohatgi

Pradeep Kumar Rohatgi 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).

  • Publication number: 20200149140
    Abstract: This invention relates to structures and processing imparting self-healing characteristics in Iron, Copper, Zinc, Magnesium, Nickel, Titanium, Gold, Silver and their alloys, and other materials including polymers and ceramics. The composite disclosed consists of a matrix with dispersed hollow macro, micro and nanotubes or balloons or fibers encapsulating a lower melting point or liquid healing material; self-healing results from flow of liquid “healing agent” into the crack. Another type of self-healing material is where the cracks are subjected to compressive stresses due to phase transformations in the matrix or reinforcement, including nano structure matrix and nanosize reinforcements. The compressive stresses could be due to shrinkage of shape memory material in the form of fibers, micro and nano size which deform, or reinforcements when expand upon reaction with atmosphere sealing the crack.
    Type: Application
    Filed: November 13, 2018
    Publication date: May 14, 2020
    Inventor: Pradeep Kumar Rohatgi
  • Patent number: 10161026
    Abstract: The invention discloses the internal structures and processes to synthesize the structure of self-healing materials, especially metallic materials, metal matrix micro and nanocomposites. Self-healing is imparted by incorporation of macro, micro or nanosize hollow reinforcements including nanotubes, filled with low melting healing material or incorporation of healing material in pockets within the metallic matrix; the healing material melts and fills the crack. In another concept, macro, micro and nanosize solid reinforcements including ceramic and metallic particles, and shape memory alloys are incorporated into alloy matrices, specially nanostructured alloy matrices, to impart self healing by applying compressive stresses on the crack or diffusing material into voids to fill them.
    Type: Grant
    Filed: July 21, 2016
    Date of Patent: December 25, 2018
    Inventor: Pradeep Kumar Rohatgi
  • Patent number: 9435014
    Abstract: The invention discloses the internal structures and processes to synthesize the structure of self-healing materials, especially metallic materials, metal matrix micro and nanocomposites. Self-healing is imparted by incorporation of macro, micro or nanosize hollow reinforcements including nanotubes, filled with low melting healing material or incorporation of healing material in pockets within the metallic matrix; the healing material melts and fills the crack. In another concept, macro, micro and nanosize solid reinforcements including ceramic and metallic particles, and shape memory alloys are incorporated into alloy matrices, specially nanostructured alloy matrices, to impart self healing by applying compressive stresses on the crack or diffusing material into voids to fill them.
    Type: Grant
    Filed: June 27, 2013
    Date of Patent: September 6, 2016
    Inventor: Pradeep Kumar Rohatgi
  • Publication number: 20130340896
    Abstract: The invention discloses the internal structures and processes to synthesize the structure of self-healing materials, especially metallic materials, metal matrix micro and nanocomposites. Self-healing is imparted by incorporation of macro, micro or nanosize hollow reinforcements including nanotubes, filled with low melting healing material or incorporation of healing material in pockets within the metallic matrix; the healing material melts and fills the crack. In another concept, macro, micro and nanosize solid reinforcements including ceramic and metallic particles, and shape memory alloys are incorporated into alloy matrices, specially nanostructured alloy matrices, to impart self healing by applying compressive stresses on the crack or diffusing material into voids to fill them.
    Type: Application
    Filed: June 27, 2013
    Publication date: December 26, 2013
    Inventor: Pradeep Kumar Rohatgi
  • Patent number: 6183877
    Abstract: This composite consists of an aluminum-alloy matrix containing by volume percent, 0.4 to 8.8 alumina, 1 to 4.4 carbon or graphite and 0.5 to 20 nickel-bearing aluminide. The alumina particles have an average size between 3 and 250 &mgr;m and the carbon and graphite particles have an average size between 10 and 250 &mgr;m. The composite is cast by stirring alumina and carbon or graphite contained in a molten aluminum or aluminum-base alloy to form a molten mixture. The molten mixture is cast directly from a temperature above the liquidus of the matrix alloy. While solidifying, carbon or graphite particles delay or hinder the settling of alumina to create a more uniform composite structure. The resulting composite structure contains an aluminum-base alloy, alumina, carbon or graphite and nickel-bearing aluminide dispersoids.
    Type: Grant
    Filed: August 20, 1997
    Date of Patent: February 6, 2001
    Assignee: Inco Limited
    Inventors: James Alexander Evert Bell, Pradeep Kumar Rohatgi, Thomas Francis Stephenson, Anthony Edward Moline Warner
  • Patent number: 3932596
    Abstract: Kish graphite can be separated from fume in kish graphite-fume mixtures and can be recovered as a clean usable product by screening the kish graphite-fume mixtures to separate the mixtures into a screen overflow and screen underflow. The screen overflow is mixed with a solution of a washing agent and a surface active agent. The mixture is stirred to thoroughly "wet" the surfaces of the kish graphite. The mixture is filtered. The kish graphite is recovered as a filter cake. The effluent which consists of the washing agent, the surface active agent and fume, is passed to waste. The kish graphite retains its integrity through the separation, recovery, and cleaning steps.
    Type: Grant
    Filed: April 23, 1974
    Date of Patent: January 13, 1976
    Assignee: Bethlehem Steel Corporation
    Inventor: Pradeep Kumar Rohatgi