Patents by Inventor Krishnan K. Sankaran

Krishnan K. 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).

  • Patent number: 8852365
    Abstract: An aluminum alloy comprises aluminum, magnesium, scandium, and an enhancing system. The magnesium is from about 0.5 percent to about 10.0 percent by weight based on the aluminum alloy. The scandium is from about 0.05 percent to about 10.0 percent by weight based on the aluminum alloy. The enhancing system is from about 0.05 percent to about 1.5 percent by weight based on the aluminum alloy.
    Type: Grant
    Filed: January 7, 2009
    Date of Patent: October 7, 2014
    Assignee: The Boeing Company
    Inventors: Krishnan K. Sankaran, Kevin T. Slattery
  • Patent number: 8323427
    Abstract: Disclosed embodiments disclose processes for making shaped metal alloy parts, and deal more particularly with forming features and reducing residual stresses in such parts. Residual stresses introduced into a metal alloy part by heat treatment, which may include solution annealing and quenching, are reduced by processes that plastically deform the part while forming part features. An embodiment comprises: producing a metal alloy blank; subjecting the blank to a process that introduces residual stresses into the blank and plastically deforming the blank to reduce the residual stresses in the blank. Embodiments comprise: subjecting a part to a heat treatment that introduces residual stresses in the part; and age forming the part to shape the part and reduce the residual stresses, incrementally forging at least one feature into the part and reducing the residual stresses in the part, friction welding the part, or gauge rolling the cast part to desired dimensions.
    Type: Grant
    Filed: September 14, 2009
    Date of Patent: December 4, 2012
    Assignee: The Boeing Company
    Inventors: Kevin T. Slattery, Krishnan K. Sankaran, James B. Castle, Christopher S. Huskamp
  • Publication number: 20100170996
    Abstract: An aluminum alloy comprises aluminum, magnesium, scandium, and an enhancing system. The magnesium is from about 0.5 percent to about 10.0 percent by weight based on the aluminum alloy. The scandium is from about 0.05 percent to about 10.0 percent by weight based on the aluminum alloy. The enhancing system is from about 0.05 percent to about 1.5 percent by weight based on the aluminum alloy.
    Type: Application
    Filed: January 7, 2009
    Publication date: July 8, 2010
    Inventors: Krishnan K. Sankaran, Kevin T. Slattery
  • Patent number: 7614539
    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: Grant
    Filed: September 13, 2004
    Date of Patent: November 10, 2009
    Assignee: The Boeing Company
    Inventors: Krishnan K. Sankaran, Richard J. Lederich, Kevin T. Slattery
  • Patent number: 7105067
    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: Grant
    Filed: June 5, 2003
    Date of Patent: September 12, 2006
    Assignee: The Boeing Company
    Inventors: Krishnan K. Sankaran, Brian J. Sova, Henry W. Babel