Patents by Inventor K. Bhagwan Das

K. Bhagwan Das 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).

  • Method for making metal matrix composites
    Patent number: 4797155
    Abstract: A metal matrix composite is produced by plastically deforming a metal powder, either or after blending the powder with ceramic fibers, and compacting the mixture at elevated temperatures to achieve substantially full density. Imparting strain energy to the metal allows reduction of the compaction temperature to eliminate reaction between the fibers and the metal or degradation of the fibers. Silicon nitride fibers are thermodynamically superior for use in aluminum or titanium metal matrix composites, since silicon nitride fibers are more stable at the temperatures required for full compaction. Secondary phase reactions are avoided.
    Type: Grant
    Filed: February 27, 1987
    Date of Patent: January 10, 1989
    Assignee: The Boeing Company
    Inventor: K. Bhagwan Das
  • Metal matrix composite fiber reinforced weld
    Patent number: 4752537
    Abstract: A welded article, comprising at least one fiber reinforced metal matrix composite joined to another article with a weld having a composition of matrix metal and between about 12-20 volume percent reinforcing fibers to strengthen the weld over that of unreinforced matrix metal welds.
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: June 21, 1988
    Assignee: The Boeing Company
    Inventor: K. Bhagwan Das
  • Metal matrix composites and method of manufacture
    Patent number: 4699849
    Abstract: A metal matrix composite is produced by plastically deforming a metal powder, either before or after blending the powder with ceramic fibers, and compacting the mixture at elevated temperatures to achieve substantially full density. Imparting strain energy to the metal allows reduction of the compaction temperature to eliminate reaction between the fibers and the metal or degradation of the fibers. Silicon nitride fibers are thermodynamically superior for use in aluminum or titanium metal matrix composites, since silicon nitride fibers are more stable at the temperatures required for full compaction. Secondary phase reactions are avoided.
    Type: Grant
    Filed: July 17, 1985
    Date of Patent: October 13, 1987
    Assignee: The Boeing Company
    Inventor: K. Bhagwan Das
  • Weld rod
    Patent number: 4683368
    Abstract: A welding method forms a fiber reinforced weld in a fiber metal matrix composite. Novel weld rods or consumable electrodes for introducing the fibers to the molten weld pool are disclosed. Reinforcing fibers are added to a molten weld pool that is initially substantially free of fibers. The fibers strengthen the weld. The concentration of the fiber should be controlled so that the viscosity of the pool remains suitable for welding.
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: July 28, 1987
    Assignee: The Boeing Company
    Inventor: K. Bhagwan Das
  • Method of welding metal matrix composites
    Patent number: 4625095
    Abstract: A welding method forms a fiber reinforced weld in a fiber metal matrix composite. Novel weld rods or consumable electrodes for introducing the fibers to the molten weld pool are disclosed. Reinforcing fibers are added to a molten weld pool that is initially substantially free of fibers. The fibers strengthen the weld. The concentration of the fiber should be controlled so that the viscosity of the pool remains suitable for welding.
    Type: Grant
    Filed: June 10, 1985
    Date of Patent: November 25, 1986
    Assignee: The Boeing Company
    Inventor: K. Bhagwan Das