Patents by Inventor Sridhar Bushigampala

Sridhar Bushigampala 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).

  • Enhanced techniques for production of golden bronze by inter-diffusion of tin and copper under controlled conditions
    Patent number: 10266959
    Abstract: Golden bronze appearance article, multiple-layer substrate, related methods and uses thereof, particularly for coinage blanks. Methods of producing an article having a golden bronze appearance include annealing a multiple-layer substrate at an annealing temperature for an annealing residence time. The multiple-layer substrate includes a core, contiguous to a copper layer and subsequent tin layer. The annealing temperature and annealing residence time are controlled in accordance with each other for allowing diffusion of the tin layer into the copper layer and producing an annealed substrate comprising an inter-diffused outer bronze layer having a golden appearance. The tin layer thickness is in accordance to the copper layer thickness such that the inter-diffused outer bronze layer has a tin content between about 8% wt. and about 15.8% wt. The core has a sufficiently low content of nickel to reduce or prevent formation of intermetallic compound comprising tin and nickel proximate to the core during annealing.
    Type: Grant
    Filed: November 8, 2012
    Date of Patent: April 23, 2019
    Assignee: MONNAIE ROYALE CANADIENNE / ROYAL CANADIAN MINT
    Inventors: Taixiang Jiang, Sridhar Bushigampala, Xianyao Li
  • Enhanced Techniques For Production of Golden Bronze By Inter-Diffusion of Tin and Copper Under Controlled Conditions
    Publication number: 20150267312
    Abstract: Golden bronze appearance article, multiple-layer substrate, related methods and uses thereof, particularly for coinage blanks. Methods of producing an article having a golden bronze appearance include annealing a multiple-layer substrate at an annealing temperature for an annealing residence time. The multiple-layer substrate includes a core, contiguous to a copper layer and subsequent tin layer. The annealing temperature and annealing residence time are controlled in accordance with each other for allowing diffusion of the tin layer into the copper layer and producing an annealed substrate comprising an inter-diffused outer bronze layer having a golden appearance. The tin layer thickness is in accordance to the copper layer thickness such that the inter-diffused outer bronze layer has a tin content between about 8% wt. and about 15.8% wt. The core has a sufficiently low content of nickel to reduce or prevent formation of intermetallic compound comprising tin and nickel proximate to the core during annealing.
    Type: Application
    Filed: November 8, 2012
    Publication date: September 24, 2015
    Inventors: Taixiang Jiang, Sridhar Bushigampala, Xianyao Li