Patents by Inventor Roger D. Doherty

Roger D. Doherty 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: 6322646
    Abstract: A method for making a superplastically formable, aluminum alloy product which consists essentially of: about 2-3.8 wt. % magnesium; at least one dispersoid-forming element selected from the group consisting of: up to about 1.6 wt. % manganese, up to about 0.2 wt. % zirconium, and up to about 0.3 w. % chromium; at least one nucleation-enhancing element for recrystallization selected from: about 0.11-1.0 wt. % silicon, up to about 1.5 wt. % copper, and combinations thereof. Said alloy product has greater than about 300% elongation at a strain rate of about 0.0001-0.003/sec and a superplastic forming temperature between about 1000-1100° F. due, in part to the preferred thermomechanical processing steps applied to its intermediate plate or slab product forms.
    Type: Grant
    Filed: June 12, 2000
    Date of Patent: November 27, 2001
    Assignee: Alcoa Inc.
    Inventors: Dhruba J. Chakrabarti, Roger D. Doherty
  • Patent number: 6063210
    Abstract: A superplastically formable, aluminum alloy product which consists essentially of about 2-10 wt. % magnesium; at least one dispersoid-forming element selected from the group consisting of: up to about 1.6 wt. % manganese, up to about 0.2 wt. % zirconium, and up to about 0.3 w. % chromium; at least one nucleation-enhancing element for recrystallization selected from: up to about 1.0 wt. % silicon, up to about 1.5 wt. % copper, and combinations thereof. Said alloy product has greater than about 300% elongation at a strain rate of at least about 0.0003/sec and a superplastic forming temperature between about 1000-1100.degree. F. due, in part, to the preferred thermomechanical processing steps subsequently applied thereto. A related method of manufacture is also disclosed herein.
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: May 16, 2000
    Assignee: Aluminum Company of America
    Inventors: Dhruba J. Chakrabarti, Roger D. Doherty
  • Patent number: 5192378
    Abstract: Disclosed is a method for making an aluminum alloy sheet having controlled levels of strength properties for forming into a container panel. A body of an aluminum alloy consisting essentially of 0.45 to 0.60 wt. % Cu, 1.1 to 1.7 wt. % Mg, 0.3 to 0.6 wt. % Si, 0.3 to 0.55 wt. % Fe, 0.5 to 1.2 wt. % Mn, the remainder aluminum, incidental elements and impurities, is hot rolled to a gauge in the range of 0.12 to 0.16 inch to provide a hot rolled product. The hot rolled product is cold rolled to provide a reduction of 50 to 80% in thickness, then solution heat treated in a range of 850.degree. to 110.degree. F. and rapidly cooled before cold rollign to a final sheet gauge by providing a reduction of 30 to 90% in thickness.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: March 9, 1993
    Assignee: Aluminum Company of America
    Inventors: Roger D. Doherty, John Liu, Robert E. Sanders, Jr.
  • Patent number: 5169463
    Abstract: A work-strengthenable alloy which includes a gamma prime phase gamma prime particles comprising the following elements in percent by weight:______________________________________ molybdenum 6-16 chromium 13-25 iron 0-23 nickel 10-55 carbon 0-0.05 boron 0-0.05 cobalt balance, at least 20, ______________________________________said alloy also containing one or more elements which form gamma prime phase with nickel,the electron vacancy number, N.sub.v, of the alloy being defined byN.sub.v =0.61 Ni+1.71 Co+2.66 Fe+4.66 Cr+566 Mowherein the respective chemical symbols represent the effective atomic fractions of the respective elements present in the alloy, said value not exceeding the valueN.sub.v =2.82-0.017 W.sub.Fe,where W.sub.Fe is the percent by weight of iron in the alloy for those alloys containing no iron or less than 13 percent by weight iron and W.sub.Fe is 13 for the alloys containing from 13-23 percent by weight iron. The alloys are formed by a melt; and heating the alloy at a temperature of from 600.
    Type: Grant
    Filed: February 19, 1991
    Date of Patent: December 8, 1992
    Assignee: SPS Technologies, Inc.
    Inventors: Roger D. Doherty, Rishi P. Singh
  • Patent number: 4931255
    Abstract: This invention relates to a nickel-cobalt alloy comprising the following elements in percent by weight:______________________________________ Carbon about 0-0.05 Molybdenum about 6-11 Iron about 0-1 Titanium about 0-6 Chromium about 15-23 Boron about 0.005-0.020 Columbium about 1.1-10 Aluminum about 0.4-4.0 Cobalt about 30-60 Nickel balance ______________________________________the alloy having an electron vacancy number, N.sub.v, defined by N.sub.v =0.61 Ni+1.71 Co+2.66 Fe+4.66 Cr+5.66 Mo wherein the respective chemical symbols represent the effective atomic fractions of the respective elements present in the alloy, the value not exceeding the value N.sub.v =2.82-0.017 W.sub.Fe, wherein W.sub.Fe is the percent by weight of iron in the alloy.In one aspect, the alloy of the present invention is preferably finally cold worked at ambient temperature to a reduction in cross-section of at least 5% and up to about 40%, although higher levels of cold work may be used with some loss of thermomechanical properties.
    Type: Grant
    Filed: December 2, 1988
    Date of Patent: June 5, 1990
    Assignee: SPS Technologies, Inc.
    Inventors: Roger D. Doherty, Rishi P. Singh, John S. Slaney
  • Patent number: 4908069
    Abstract: A method of making a work-strengthenable alloy which includes a gamma prime phase which method comprises forming a melt comprising the following elements in percent by weight:______________________________________ molybdenum 6-16 chromium 13-25 iron 0-23 nickel 10-55 carbon 0-0.05 boron 0-0.05 cobalt balance, at least 20, ______________________________________said alloy also containing one or more elements which form gamma prime phase with nickel, the electron vacancy number, N.sub.v, of the alloy being defined byN.sub.v =0.61 Ni+1.71 Co+2.66 Fe+4.66 Cr+5.66 Mowherein the respective chemical symbols represent the effective atomic fractions of the respective elements present in the alloy, said value not exceeding the valueN.sub.v =2.82-0.017 W.sub.Fe,where W.sub.Fe is the percent by weight of iron in the alloy for those alloys containing no iron or less than 13 percent by weight iron and W.sub.
    Type: Grant
    Filed: October 19, 1987
    Date of Patent: March 13, 1990
    Assignee: SPS Technologies, Inc.
    Inventors: Roger D. Doherty, Rishi P. Singh
  • Patent number: 4659396
    Abstract: A method including providing aluminum having particles for stimulating nucleation of new grains, and deforming the aluminum under conditions for causing recrystallization to occur during deformation or thereafter, without subsequent heating being required to effect recrystallization.
    Type: Grant
    Filed: July 30, 1984
    Date of Patent: April 21, 1987
    Assignee: Aluminum Company of America
    Inventors: Bernard W. Lifka, John Liu, Roger D. Doherty