Patents by Inventor Krishnan Sankaran

Krishnan Sankaran 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: 20060054252
    Abstract: A method for forming an aluminum alloy article having improved mechanical properties using a solid-state joining process in which the problem of ductility reduction is minimized by conducting a thermal exposure treatment prior to solution heat treatment. This thermal exposure treatment, done at a temperature below the solution heat treatment temperature, releases stored energy in the aluminum-alloy material. The aluminum-alloy material then does not have sufficient energy to cause recrystallization and abnormal grain growth during the subsequent solution heat treatment process. The resultant aluminum-alloy material has a restored mechanical strength with only a minor, but acceptable, decrease in original ductility.
    Type: Application
    Filed: September 13, 2004
    Publication date: March 16, 2006
    Inventors: Krishnan Sankaran, Richard Lederich, Kevin Slattery
  • Publication number: 20050284552
    Abstract: A method to increase the toughness of the aluminum-lithium alloy C458 and similar alloys at cryogenic temperatures above their room temperature toughness is provided. Increasing the cryogenic toughness of the aluminum-lithium alloy C458 allows the use of alloy C458 for cryogenic tanks, for example for launch vehicles in the aerospace industry. A two-step aging treatment for alloy C458 is provided. A specific set of times and temperatures to age the aluminum-lithium alloy C458 to T8 temper is disclosed that results in a higher toughness at cryogenic temperatures compared to room temperature. The disclosed two-step aging treatment for alloy 458 can be easily practiced in the manufacturing process, does not involve impractical heating rates or durations, and does not degrade other material properties.
    Type: Application
    Filed: June 5, 2003
    Publication date: December 29, 2005
    Applicant: The Boeing Company
    Inventors: Krishnan Sankaran, Brian Sova, Henry Babel
  • Patent number: 5380648
    Abstract: Induction of virulence related proteins in virulent pathogenic E. coli and Shigella by growing such bacteria in the presence of Congo Red as induction triggering factor, and the application of the induction for purposes of diagnosing virulent pathogens and their antibiotic sensitivity.
    Type: Grant
    Filed: April 5, 1990
    Date of Patent: January 10, 1995
    Assignee: Aktiebolaget Astra
    Inventors: Shanmugam Elango, Shantha Rajarathnam, Vasanthi Ramachandran, Raman K. Roy, Krishnan Sankaran, Yerramilli V. B. Subrahmanyam