Patents by Inventor Dhurba J. Chakrabarti

Dhurba J. Chakrabarti 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: 8673209
    Abstract: Aluminum alloy products about 4 inches thick or less that possesses the ability to achieve, when solution heat treated, quenched, and artificially aged, and in parts made from the products, an improved combination of strength, fracture toughness and corrosion resistance, the alloy consisting essentially of: about 6.8 to about 8.5 wt. % Zn, about 1.5 to about 2.00 wt. % Mg, about 1.75 to about 2.3 wt. % Cu; about 0.05 to about 0.3 wt. % Zr, less than about 0.1 wt. % Mn, less than about 0.05 wt. % Cr, the balance Al, incidental elements and impurities and a method for making same. The invention alloy is useful in making structural members for commercial airplanes including, but not limited to, upper wing skins and stringers, spar caps, spar webs and ribs of either built-up or integral construction. The invention alloy may be aged by 2 or 3 step practices while exceeding the SCC requirements for applications for which the invention alloy is primarily intended.
    Type: Grant
    Filed: May 14, 2007
    Date of Patent: March 18, 2014
    Assignee: Alcoa Inc.
    Inventors: Gary H. Bray, Dhurba J. Chakrabarti, Diana Denzer, Jen Lin, John Newman, Greg Venema, Cagatay Yanar