Patents by Inventor Amiya K. Mukherjee

Amiya K. Mukherjee 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: 7481267
    Abstract: Ceramic materials are converted to materials with anisotropic thermal properties, electrical properties, or both, by forming the ceramics into composites with carbon nanotubes dispersed therein and uniaxially compressing the composites in a direction in which a lower thermal or electrical conductivity is desired.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: January 27, 2009
    Assignee: The Regents of the University of California
    Inventors: Guodong Zhan, Joshua D. Kuntz, Amiya K. Mukherjee
  • Publication number: 20080314568
    Abstract: Ceramic materials are converted to materials with anisotropic thermal properties, electrical properties, or both, by forming the ceramics into composites with carbon nanotubes dispersed therein and uniaxially compressing the composites in a direction in which a lower thermal or electrical conductivity is desired.
    Type: Application
    Filed: May 24, 2005
    Publication date: December 25, 2008
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, a California corporation.
    Inventors: Guodong Zhan, Joshua D. Kuntz, Amiya K. Mukherjee
  • Patent number: 7217386
    Abstract: High-density composites of alumina and titania with nano-sized grains are prepared from aluminum titanate without the need to use nano-sized powder as a starting material. The preparation is achieved by high-energy ball milling of the aluminum titanate followed by sintering at elevated temperature and pressure. The aluminum titanate can be prepared from micron-sized alumina and titania particles through plasma jet processing.
    Type: Grant
    Filed: August 2, 2004
    Date of Patent: May 15, 2007
    Assignee: The Regents of the University of California
    Inventors: Julin Wan, Amiya K. Mukherjee
  • Patent number: 7148480
    Abstract: Optical windows for protecting infrared sensing instruments are manufactured from nano-sized crystallites by compressing the crystallites into a continuous mass under high pressure in the presence of a pulsed electric current, preferably one produced by spark plasma sintering. The resulting materials have excellent optical and mechanical properties that make them favorable as replacements for the conventional single-crystal sapphire.
    Type: Grant
    Filed: July 14, 2004
    Date of Patent: December 12, 2006
    Assignee: The Regents of the University of California
    Inventors: Guodong Zhan, Amiya K. Mukherjee, Subhash H. Risbud
  • Patent number: 7128850
    Abstract: Composite materials containing silicon, titanium, carbon, and nitrogen, formed by spark plasma sintering of ceramic starting materials to a high relative density, demonstrate unusually high electrical conductivity as well as high-performance mechanical and chemical properties including hardness, fracture toughness, and corrosion resistance. This combination of electrical, mechanical, and chemical properties makes these composites useful as electrical conductors in applications where high-performance materials are needed due to exposure to extreme conditions such as high temperatures, mechanical stresses, and corrosive environments.
    Type: Grant
    Filed: June 2, 2003
    Date of Patent: October 31, 2006
    Assignee: The Regents of the University of California
    Inventors: Ren-Guan Duan, Joshua D. Kuntz, Amiya K. Mukherjee
  • Patent number: 7077991
    Abstract: Densified composites of silicon nitride, silicon carbide, and boron nitride that exhibit high creep resistance are obtained by sintering a mixture of amorphous powders of silicon nitride, silicon carbide, and boron nitride in the presence of an electric field under high pressure. The grain size in the resulting composite is less than 100 nanometers for all components of the composite, and the composite exhibits high creep resistance.
    Type: Grant
    Filed: February 6, 2004
    Date of Patent: July 18, 2006
    Assignee: The Regents of the University of California
    Inventors: Julin Wan, Amiya K. Mukherjee, Matthew J. Gasch
  • Patent number: 7029613
    Abstract: Densified composites of silicon nitride and silicon carbide that exhibit high creep resistance are obtained by mechanically activating a mixture of amorphous powders of silicon nitride and silicon carbide and sintering the mechanically activated mixture in the presence of an electric field under high pressure. The grain size in the resulting composite is less than 100 nanometers for all components of the composite, and the composite exhibits high creep resistance.
    Type: Grant
    Filed: September 8, 2003
    Date of Patent: April 18, 2006
    Assignee: The Regents of the University of California
    Inventors: Julin Wan, Matthew J. Gasch, Amiya K. Mukherjee
  • Patent number: 6976532
    Abstract: Ceramic materials are converted to materials with anisotropic thermal properties by forming the ceramics into composites with carbon nanotubes dispersed therein and uniaxially compressing the composites in a direction in which a lower thermal conductivity is desired.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: December 20, 2005
    Assignee: The Regents of the University of California
    Inventors: Guodong Zhan, Joshua D. Kuntz, Amiya K. Mukherjee
  • Patent number: 6905649
    Abstract: A nano-sized powder of barium titanate is compacted and sintered by spark plasma sintering under conditions creating a high heating rate to achieve a densified material that demonstrates superior permittivity.
    Type: Grant
    Filed: April 11, 2003
    Date of Patent: June 14, 2005
    Assignee: The Regents of the University of California
    Inventors: Guodong Zhan, Amiya K. Mukherjee, Joshua D. Kuntz, Julin Wan
  • Patent number: 6875374
    Abstract: Composite materials formed of a matrix of fused ceramic grains with single-wall carbon nanotubes dispersed throughout the matrix and a high relative density, notably that achieved by electric field-assisted sintering, demonstrate unusually high electrical conductivity in combination with high-performance mechanical properties including high fracture toughness. This combination of electrical and mechanical properties makes these composites useful as electrical conductors in applications where high-performance materials are needed due to exposure to extreme conditions such as high temperatures and mechanical stresses.
    Type: Grant
    Filed: February 26, 2003
    Date of Patent: April 5, 2005
    Assignee: The Regents of the University of California
    Inventors: Guodong Zhan, Joshua D. Kuntz, Amiya K. Mukherjee
  • Patent number: 6858173
    Abstract: Composites of ceramic materials, notably alumina or metal oxides in general, with single-wall carbon nanotubes are consolidated by electric field-assisted sintering to achieve a fully dense material that has an unusually high fracture toughness compared to the ceramic alone, and also when compared to composites that contain multi-wall rather than single-wall carbon nanotubes, and when compared to composites that are sintered by methods that do not include exposure to an electric field.
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: February 22, 2005
    Assignee: The Regents of the University of California
    Inventors: Guodong Zhan, Amiya K. Mukherjee, Joshua D. Kuntz, Julin Wan
  • Publication number: 20040261978
    Abstract: Ceramic materials are converted to materials with anisotropic thermal properties by forming the ceramics into composites with carbon nanotubes dispersed therein and uniaxially compressing the composites in a direction in which a lower thermal conductivity is desired.
    Type: Application
    Filed: June 26, 2003
    Publication date: December 30, 2004
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, a California corporation
    Inventors: Guodong Zhan, Joshua D. Kuntz, Amiya K. Mukherjee
  • Publication number: 20040238795
    Abstract: Composite materials containing silicon, titanium, carbon, and nitrogen, formed by spark plasma sintering of ceramic starting materials to a high relative density, demonstrate unusually high electrical conductivity as well as high-performance mechanical and chemical properties including hardness, fracture toughness, and corrosion resistance. This combination of electrical, mechanical, and chemical properties makes these composites useful as electrical conductors in applications where high-performance materials are needed due to exposure to extreme conditions such as high temperatures, mechanical stresses, and corrosive environments.
    Type: Application
    Filed: June 2, 2003
    Publication date: December 2, 2004
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, a California corporation
    Inventors: Ren-Guan Duan, Joshua D. Kuntz, Amiya K. Mukherjee
  • Publication number: 20040201137
    Abstract: A nano-sized powder of barium titanate is compacted and sintered by spark plasma sintering under conditions creating a high heating rate to achieve a densified material that demonstrates superior permittivity.
    Type: Application
    Filed: April 11, 2003
    Publication date: October 14, 2004
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, a California corporation
    Inventors: Guodong Zhan, Amiya K. Mukherjee, Joshua D. Kuntz, Julin Wan
  • Publication number: 20040179969
    Abstract: Densified composites of silicon nitride and silicon carbide that exhibit high creep resistance are obtained by mechanically activating a mixture of amorphous powders of silicon nitride and silicon carbide and sintering the mechanically activated mixture in the presence of an electric field under high pressure. The grain size in the resulting composite is less than 100 nanometers for all components of the composite, and the composite exhibits high creep resistance.
    Type: Application
    Filed: September 8, 2003
    Publication date: September 16, 2004
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, a California corporation
    Inventors: Julin Wan, Matthew J. Gasch, Amiya K. Mukherjee
  • Publication number: 20040167009
    Abstract: High-density composites of ceramic materials, notably alumina or metal oxides in general, are formed by the incorporation of metal particles, of which niobium is a preferred example, and single-wall carbon nanotubes. The composites demonstrate an unusually high fracture toughness compared to the ceramic alone, and also when compared to composites that contain either the metal alone or single-wall carbon nanotubes alone. The two additives thus demonstrate a synergistic effect in improving the toughness of the ceramic.
    Type: Application
    Filed: February 26, 2003
    Publication date: August 26, 2004
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, a California corporation
    Inventors: Joshua D. Kuntz, Guodong Zhan, Amiya K. Mukherjee
  • Publication number: 20040150140
    Abstract: Composites of ceramic materials, notably alumina or metal oxides in general, with single-wall carbon nanotubes are consolidated by electric field-assisted sintering to achieve a fully dense material that has an unusually high fracture toughness compared to the ceramic alone, and also when compared to composites that contain multi-wall rather than single-wall carbon nanotubes, and when compared to composites that are sintered by methods that do not include exposure to an electric field.
    Type: Application
    Filed: January 30, 2003
    Publication date: August 5, 2004
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Guodong Zhan, Amiya K. Mukherjee, Joshua D. Kuntz, Julin Wan
  • Patent number: 5728637
    Abstract: Alumina composites of unusually high hardness and toughness are formed by combining alumina and diamond in nanocrystalline form, followed by sintering at high pressure.
    Type: Grant
    Filed: February 1, 1996
    Date of Patent: March 17, 1998
    Assignee: The Regents of the University of California
    Inventors: Rajiv S. Mishra, Amiya K. Mukherjee, Charles E. Lesher