Patents by Inventor Sri Krishna Chimbli

Sri Krishna Chimbli 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: 8960523
    Abstract: When a friction stir weld tool penetrates the interface of two workpieces of dissimilar metal alloy materials, the resultant weld of the different alloy materials may produce a weak weld joint. Such weak joints are often experienced, for example, when attempting to form spot welds or other friction stir welds between a magnesium alloy sheet or strip and an aluminum alloy sheet or strip. It is discovered that suitable coating compositions including an adhesive placed at the interface of assembled workpieces can alter the composition of the friction stir weld material and strengthen the resulting bond. In the example of friction stir welds between magnesium alloy and aluminum alloy workpieces, it is found that combinations of an adhesive with copper, tin, zinc, and/or other powders can strengthen the magnesium-containing and aluminum-containing friction stir weld material.
    Type: Grant
    Filed: May 18, 2011
    Date of Patent: February 24, 2015
    Assignee: GM Global Technology Operations LLC
    Inventors: Robert T. Szymanski, Sri Krishna Chimbli, Mark T. Hall, Yen-Lung Chen
  • Publication number: 20110214799
    Abstract: When a friction stir weld tool penetrates the interface of two workpieces of dissimilar metal alloy materials, the resultant weld of the different alloy materials may produce a weak weld joint. Such weak joints are often experienced, for example, when attempting to form spot welds or other friction stir welds between a magnesium alloy sheet or strip and an aluminum alloy sheet or strip. It is discovered that suitable coating compositions including an adhesive placed at the interface of assembled workpieces can alter the composition of the friction stir weld material and strengthen the resulting bond. In the example of friction stir welds between magnesium alloy and aluminum alloy workpieces, it is found that combinations of an adhesive with copper, tin, zinc, and/or other powders can strengthen the magnesium-containing and aluminum-containing friction stir weld material.
    Type: Application
    Filed: May 18, 2011
    Publication date: September 8, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Robert T. Szymanski, Sri Krishna Chimbli, Mark T. Hall, Yen-Lung Chen
  • Patent number: 7997472
    Abstract: When a friction stir weld tool penetrates the interface of two workpieces of dissimilar metal alloy materials, the resultant weld of the different alloy materials may produce a weak weld joint. Such weak joints are often experienced, for example, when attempting to form spot welds or other friction stir welds between a magnesium alloy sheet or strip and an aluminum alloy sheet or strip. It is discovered that suitable coating compositions including an adhesive placed at the interface of assembled workpieces can alter the composition of the friction stir weld material and strengthen the resulting bond. In the example of friction stir welds between magnesium alloy and aluminum alloy workpieces, it is found that combinations of an adhesive with copper, tin, zinc, and/or other powders can strengthen the magnesium-containing and aluminum-containing friction stir weld material.
    Type: Grant
    Filed: April 6, 2009
    Date of Patent: August 16, 2011
    Assignee: GM Global Technology Operations LLC
    Inventors: Robert T. Szymanski, Sri Krishna Chimbli, Mark T. Hall, Yen-Lung Chen
  • Publication number: 20100089977
    Abstract: When a friction stir weld tool penetrates the interface of two workpieces of dissimilar metal alloy materials, the resultant weld of the different alloy materials may produce a weak weld joint. Such weak joints are often experienced, for example, when attempting to form spot welds or other friction stir welds between a magnesium alloy sheet or strip and an aluminum alloy sheet or strip. It is discovered that suitable coating compositions placed at the interface of assembled workpieces can alter the composition of the friction stir weld material and strengthen the resulting bond. In the example of friction stir welds between magnesium alloy and aluminum alloy workpieces, it is found that combinations of copper, tin, and zinc, and other powders can strengthen the magnesium-containing and aluminum-containing friction stir weld material.
    Type: Application
    Filed: October 14, 2008
    Publication date: April 15, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Yen-Lung Chen, Sri Krishna Chimbli, Mark T. Hall, Xiaohong Q. Gayden, Robert T. Szymanski
  • Publication number: 20100089976
    Abstract: When a friction stir weld tool penetrates the interface of two workpieces of dissimilar metal alloy materials, the resultant weld of the different alloy materials may produce a weak weld joint. Such weak joints are often experienced, for example, when attempting to form spot welds or other friction stir welds between a magnesium alloy sheet or strip and an aluminum alloy sheet or strip. It is discovered that suitable coating compositions including an adhesive placed at the interface of assembled workpieces can alter the composition of the friction stir weld material and strengthen the resulting bond. In the example of friction stir welds between magnesium alloy and aluminum alloy workpieces, it is found that combinations of an adhesive with copper, tin, zinc, and/or other powders can strengthen the magnesium-containing and aluminum-containing friction stir weld material.
    Type: Application
    Filed: April 6, 2009
    Publication date: April 15, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Robert T. Szymanski, Sri Krishna Chimbli, Mark T. Hall, Yen-Lung Chen