Patents by Inventor Murali Madhava

Murali Madhava 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: 7645485
    Abstract: There is provided a method for applying an improved chromium diffusion coating on an industrial item such as a turbine blade of a gas turbine engine. Chromium and other active metals are combined to form an alloy coating. Active elements include silicon, hafnium, zirconium, yttrium, tantalum, and rhenium. For producing the modified coatings through pack cementation chromium and a master alloy are mixed into a packing along with inert material and a halide activator. The packing surrounds a target in a diffusion box. The metals are then deposited by diffusion onto a target surface by pack cementation methods. The diffusion of the desired metals takes place during a coating thermal cycle. Alternatively, the diffusion can take place using an out-of-pack arrangement. Such modified coatings are utilized as improved performance coatings for environmental resistance applications over the current chromium diffusion coatings.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: January 12, 2010
    Assignee: Honeywell International Inc.
    Inventor: Murali Madhava
  • Publication number: 20090297704
    Abstract: There is provided a method for applying an improved chromium diffusion coating on an industrial item such as a turbine blade of a gas turbine engine. Chromium and other active metals are combined to form an alloy coating. Active elements include silicon, hafnium, zirconium, yttrium, tantalum, and rhenium. For producing the modified coatings through pack cementation chromium and a master alloy are mixed into a packing along with inert material and a halide activator. The packing surrounds a target in a diffusion box. The metals are then deposited by diffusion onto a target surface by pack cementation methods. The diffusion of the desired metals takes place during a coating thermal cycle. Alternatively, the diffusion can take place using an out-of-pack arrangement. Such modified coatings are utilized as improved performance coatings for environmental resistance applications over the current chromium diffusion coatings.
    Type: Application
    Filed: April 30, 2004
    Publication date: December 3, 2009
    Inventor: Murali Madhava
  • Publication number: 20070184305
    Abstract: A quasi-single phase or single phase thick platinum nickel aluminide coating and methods for forming the coating over a nickel-based superalloy substrate are provided. The method includes the steps of forming a metal layer over a surface of the nickel-based superalloy substrate, the metal layer comprising platinum, growing a diffusion zone comprising a platinum nickel alloy layer from the metal layer and the nickel-based superalloy substrate, and subjecting the platinum nickel alloy to one or more aluminization cycles to transform the platinum nickel alloy into a platinum nickel aluminide coating having a platinum aluminide phase formed therein.
    Type: Application
    Filed: February 7, 2006
    Publication date: August 9, 2007
    Inventors: Murali Madhava, George Reimer, Amol Gholkar
  • Patent number: 7250081
    Abstract: Methods for repair of single crystal superalloys by laser welding and products thereof have been disclosed. The laser welding process may be hand held or automated. Laser types include: CO2, Nd:YAG, diode and fiber lasers. Parameters for operating the laser process are disclosed. Filler materials, which may be either wire or powder superalloys are used to weld at least one portion of a single crystal superalloy substrate.
    Type: Grant
    Filed: December 4, 2003
    Date of Patent: July 31, 2007
    Assignee: Honeywell International, Inc.
    Inventors: Yiping Hu, William F. Hehmann, Murali Madhava
  • Patent number: 7229701
    Abstract: The present invention provides a chromium and active elements modified platinum aluminide coating that may be used on a surface of a gas turbine engine component such as a turbine blade. The coating may be used as a protective coating that impedes the progress of corrosion, oxidation, and sulfidation in superalloy materials that comprise the substrate of the turbine blade. Additionally, the coating may be used as a bond coat onto which a thermal barrier coating is deposited. The presence of active elements as well as chromium and platinum provides improved corrosion, oxidation, and sulfidation resistance. The coating is applied using an electron beam physical vapor deposition. The coating is applied alternatively using selected sequential diffusion processing steps involving chromium, platinum and aluminum.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: June 12, 2007
    Assignee: Honeywell International, Inc.
    Inventors: Murali Madhava, Timothy R. Duffy, Margaret Floyd, George Reimer
  • Publication number: 20060240192
    Abstract: The present invention provides methods and materials for use in applying a coating on a surface of a magnesium component. The method includes the steps of: accelerating a coating powder to a velocity of between about 500 to about 1200 meters/second, wherein the coating powder comprises a material selected from the group consisting of aluminum, aluminum alloys, titanium, titanium alloys, and composites; directing the coating powder through a convergent-divergent nozzle onto the surface of the magnesium component; and forming a coating on the surface of the magnesium component so as to substantially cover the surface of the magnesium component. The coating thickness may be between approximately 0.1 to approximately 1.0 mm.
    Type: Application
    Filed: April 25, 2005
    Publication date: October 26, 2006
    Inventors: Derek Raybould, Murali Madhava, Vincent Chung, Timothy Duffy, Margaret Floyd
  • Publication number: 20060222776
    Abstract: In a method for coating a surface of a turbine component with an environment-resistant aluminide, a coating is formed by cold gas-dynamic spraying a powder material on the turbine component surface, the powder material comprising aluminum, platinum, and at least one additional metal selected from the group consisting of nickel, chromium, hafnium, silicon, yttrium, rhenium, zirconium, cobalt, and tantalum. After forming the coating, at least one thermal diffusion treatment is performed on the turbine component to metallurgically homogenize the coating and thereby form an aluminide coating that includes by weight about 12 to about 30% aluminum, up to about 50% platinum, about 2 to about 25% chromium, about 1 to about 5% hafnium, about 1 to about 5% silicon, about 0.1 to about 1% yttrium, and about 1 to about 3% Zr, and nickel.
    Type: Application
    Filed: March 29, 2005
    Publication date: October 5, 2006
    Inventors: Murali Madhava, Yiping Hu, Derek Raybould, Trinh-Le Huu-Duc, Siu-Ching Lui
  • Publication number: 20060166020
    Abstract: The present invention thus provides an improved method for coating turbine engine components. The method utilizes a cold high velocity gas spray technique to coat turbine blades, compressor blades, impellers, blisks, and other turbine engine components. These methods can be used to coat a variety of surfaces thereon, thus improving the overall durability, reliability and performance of the turbine engine itself. The method includes the deposition of powders of alloys of nickel and aluminum wherein the powders are formed so as to have an amorphous microstructure. Layers of the alloys may be deposited and built up by cold high velocity gas spraying. The coated items displayed improved characteristics such as hardness, strength, and corrosion resistance.
    Type: Application
    Filed: January 26, 2005
    Publication date: July 27, 2006
    Inventors: Derek Raybould, Murali Madhava
  • Publication number: 20060141283
    Abstract: The present invention provides a low cost diffused MCrAlYX type coating that may be used on a surface of gas turbine engine component such as a turbine blade. The coating may be used as a protective coating that impedes the progress of corrosion, oxidation, and sulfidation in superalloy materials that comprise the substrate of the turbine blade. The method of depositing the coating includes steps such as: (1) forming an active elements modified chromium diffusion coating; (2) depositing noble metals such as platinum to a thickness in the range of 3 to 6 microns through known procedures such as electroplating or PVD techniques; (3) performing a diffusion cycle in the temperature range of approximately 1800° F. to 2000° F.; (4) performing an aluminizing step to generate coating microstructures; and (5) optionally performing a post coat diffusion treatment in the 1900° F. to 2025° F. temperature range.
    Type: Application
    Filed: December 29, 2004
    Publication date: June 29, 2006
    Inventor: Murali Madhava
  • Publication number: 20060093736
    Abstract: A method for coating a surface of a component formed from aluminum or an alloy thereof includes the step of cold gas-dynamic spraying a powder material on the component surface to form a coating, the powder material comprising at least one alloy from the group consisting of titanium, a titanium alloy, nickel, a nickel alloy, iron, an iron alloy, aluminum, an aluminum alloy, copper, a copper alloy, cobalt, and a cobalt alloy. In one embodiment, the method further includes the step of heat treating the turbine component after the cold gas-dynamic spraying.
    Type: Application
    Filed: October 29, 2004
    Publication date: May 4, 2006
    Inventors: Derek Raybould, Murali Madhava, Vincent Chung, Timothy Duffy
  • Publication number: 20060046091
    Abstract: The present invention provides a chromium and active elements modified platinum aluminide coating that may be used on a surface of a gas turbine engine component such as a turbine blade. The coating may be used as a protective coating that impedes the progress of corrosion, oxidation, and sulfidation in superalloy materials that comprise the substrate of the turbine blade. Additionally, the coating may be used as a bond coat onto which a thermal barrier coating is deposited. The presence of active elements as well as chromium and platinum provides improved corrosion, oxidation, and sulfidation resistance. The coating is applied using an electron beam physical vapor deposition. The coating is applied alternatively using selected sequential diffusion processing steps involving chromium, platinum and aluminum.
    Type: Application
    Filed: August 26, 2004
    Publication date: March 2, 2006
    Inventors: Murali Madhava, Timothy Duffy, Margaret Floyd, George Reimer
  • Publication number: 20050265851
    Abstract: There is provided a method for applying a diffusion coating on a specific area of targeted industrial item such as a turbine blade. The method uses a covering material such as a tape or slurry to cover the area where it is desired that the diffusion occur, for example above the root area of a turbine blade. The tape material includes a metallic source such as chromium and a master alloy of active elements for diffusion. The covering material thus defines the localized patch that is to be coated. An activator if any, such as a halide activator, can be included in the tape or slurry. Alternatively, the activator can be included in the pack material. The method uses known pack cementation methods to complete the diffusive process. The method results in a diffusion coating over a specific area of the target item.
    Type: Application
    Filed: May 26, 2004
    Publication date: December 1, 2005
    Inventors: Murali Madhava, Margaret Floyd, George Reimer
  • Publication number: 20050220995
    Abstract: A new method for increasing the durability of a turbine engine is provided. The method utilizes a cold gas-dynamic spray technique to apply wear resistant materials to turbine blades. These wear resistant materials improve the durability of the turbine blades, and thus can improve the overall durability, reliability and performance of the turbine engine themselves. In the cold gas-dynamic spray process particles at a temperature below their fusing temperature are accelerated and directed to a target surface on the turbine blade. When the particles strike the target surface, the kinetic energy of the particles is converted into deformation of the particle, causing the particle to form a strong bond with the target surface. Post-spray processing is then performed to consolidate the coating materials and restore material properties in the turbine blade. Thus, the cold gas-dynamic spray process can apply a coating of wear resistant materials to the turbine blades.
    Type: Application
    Filed: April 6, 2004
    Publication date: October 6, 2005
    Inventors: Yiping Hu, Federico Renteria, Murali Madhava
  • Patent number: 6905728
    Abstract: A new method for repairing turbine engine components is provided. The method utilizes a cold gas-dynamic spray technique to repair degradation on turbine blades, vanes and other components. In the cold gas-dynamic spray process particles at a temperature below their fusing temperature are accelerated and directed to a target surface on the turbine blade. When the particles strike the target surface, the kinetic energy of the particles is converted into plastic deformation of the particle, causing the particle to form a strong bond with the target surface. Post-spray processing is then performed to consolidate and homogenize the applied materials and restore integrity to the material properties in the repaired turbine component. Thus, the cold gas-dynamic spray process and post-spray processing can be employed to effectively repair degraded areas on gas turbine components.
    Type: Grant
    Filed: March 22, 2004
    Date of Patent: June 14, 2005
    Assignee: Honeywell International, Inc.
    Inventors: Yiping Hu, Murali Madhava, Federico Renteria
  • Publication number: 20050120941
    Abstract: Methods for repair of single crystal superalloys by laser welding and products thereof have been disclosed. The laser welding process may be hand held or automated. Laser types include: CO2, Nd:YAG, diode and fiber lasers. Parameters for operating the laser process are disclosed. Filler materials, which may be either wire or powder superalloys are used to weld at least one portion of a single crystal superalloy substrate.
    Type: Application
    Filed: December 4, 2003
    Publication date: June 9, 2005
    Inventors: Yiping Hu, William Hehmann, Murali Madhava