Patents by Inventor Stephen N. Hammond

Stephen N. Hammond 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: 8480817
    Abstract: One embodiment of the present invention is a unique method for thermal mechanical processing of a martensitic stainless steel. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for thermal mechanical processing of a martensitic stainless steel and forged objects resulting therefrom. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith.
    Type: Grant
    Filed: July 11, 2010
    Date of Patent: July 9, 2013
    Assignee: Rolls-Royce Corporation
    Inventors: Sushil K. Jain, Stephen N. Hammond
  • Patent number: 8293028
    Abstract: A carburizing process for increasing the hardness of a case region of a steel component. In one form the application includes plating the outer surface of a stainless steel component with nickel prior to carburizing. One component includes a stainless steel object having a hardened case substantially free of continuous phase grain boundary carbides.
    Type: Grant
    Filed: January 19, 2010
    Date of Patent: October 23, 2012
    Assignee: Rolls-Royce Corporation
    Inventors: Stephen N. Hammond, Udayan Trivedi, Thomas L. Doubts, Douglas C. Steckbauer
  • Patent number: 8241005
    Abstract: In one embodiment a centrifugal impeller has an axis of rotation, a plurality of blades, and a plurality of pitches defined between the blades. A cavity may be formed in a back side of the impeller, opposite with at least one of the plurality of pitches. In one form the cavity may not extend below a radius determined according to a stress criteria or stress limitation.
    Type: Grant
    Filed: October 16, 2008
    Date of Patent: August 14, 2012
    Assignee: Rolls-Royce North American Technologies, Inc.
    Inventors: Calvin W. Emmerson, Robert A. Ress, Jr., Stephen N. Hammond
  • Publication number: 20110108164
    Abstract: One embodiment of the present invention is a unique method for thermal mechanical processing of a martensitic stainless steel. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for thermal mechanical processing of a martensitic stainless steel and forged objects resulting therefrom. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith.
    Type: Application
    Filed: July 11, 2010
    Publication date: May 12, 2011
    Inventors: Sushil K. Jain, Stephen N. Hammond
  • Publication number: 20110017350
    Abstract: A carburizing process for increasing the hardness of a case region of a steel component. In one form the application includes plating the outer surface of a stainless steel component with nickel prior to carburizing. One component includes a stainless steel object having a hardened case substantially free of continuous phase grain boundary carbides.
    Type: Application
    Filed: January 19, 2010
    Publication date: January 27, 2011
    Inventors: Stephen N. Hammond, Udayan Trivedi, Thomas L. Doubts, Douglas C. Steckbauer
  • Publication number: 20100098546
    Abstract: In one embodiment a centrifugal impeller has an axis of rotation, a plurality of blades, and a plurality of pitches defined between the blades. A cavity may be formed in a back side of the impeller, opposite with at least one of the plurality of pitches. In one form the cavity may not extend below a radius determined according to a stress criteria or stress limitation.
    Type: Application
    Filed: October 16, 2008
    Publication date: April 22, 2010
    Inventors: Calvin W. Emmerson, Robert A. Ress, JR., Stephen N. Hammond
  • Patent number: 7648588
    Abstract: The application contemplates a steel body having a hardened case portion and a core portion. The case portion has a hardness of at least Rc 50 and is substantially free of continuous phase grain boundary carbides. The steel body is formed of Pyrowear 675 which is a stainless steel material.
    Type: Grant
    Filed: April 18, 2007
    Date of Patent: January 19, 2010
    Assignee: Rolls-Royce Corporation
    Inventors: Stephen N. Hammond, Udayan Trivedi, Thomas L. Doubts, Douglas C. Steckbauer
  • Patent number: 7208052
    Abstract: A carburizing process for increasing the hardness of a case region of a steel component. In one form the application includes plating the outer surface of a stainless steel component with nickel prior to carburizing. One component includes a stainless steel object having a hardened case substantially free of continuous phase grain boundary carbides.
    Type: Grant
    Filed: January 27, 2004
    Date of Patent: April 24, 2007
    Assignee: Rolls-Royce Corporation
    Inventors: Stephen N. Hammond, Udayan Trivedi, Thomas L. Doubts, Douglas C. Steckbauer
  • Patent number: 6417477
    Abstract: An electrospark alloying apparatus includes a main body member, a collet coupled to the main body member, and a heat sink adjacent the collet. The collet is adapted to receive and hold a consumable electrode. The apparatus can also include a drive for rotating the electrode. Further, the apparatus can include an inert gas supply and a discharge opening in the main body member for facilitating lamellar gas flow of insert gas from the inert gas supply around the electrode. A method of electrospark alloying includes electrospark alloying a workpiece with a consumable electrode and cooling the electrode during the electrospark welding.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: July 9, 2002
    Assignee: Rolls-Royce Corporation
    Inventors: Lawrence E. Brown, Stephen N. Hammond, Mark C. Nordin
  • Patent number: 6338189
    Abstract: The present invention generally relates to an external cylindrical or conic section shaped fixture which is tightly fit around the same shaped workpiece prior to expansion forming to a final dimension. During expansion forming, the external fixture is also deformed and is therefore designed for one-time use. The external cylindrical or conic section shaped fixture of the present invention is particularly useful for expansion forming of workpieces which contain brazed lap joints. The external fixture restrains, out-of-plane joint rotation and reduces the stress concentrations existing near the lap joints. Additionally, the external fixture provides additional load carrying capability to allow better load distribution during expansion forming. No change is required to the expansion forming machinery or the inner expander dies (jaws) with use of the present invention.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: January 15, 2002
    Assignee: Allison Engine Company, Inc.
    Inventors: Raymond Ruiwen Xu, Stephen N. Hammond, Jacque B. Kennedy, Randolph C. Helmink, Robert A. Testin
  • Patent number: 6129257
    Abstract: The present invention provides a brazing fixture and method of using the fixture which allows the brazing of a joint in an oxide-dispersion-strengthened (ODS) high temperature alloy workpiece where stresses in the workpiece operate to open the joint during the brazing process. The fixture is formed from the same ODS alloy as the workpiece, such that the fixture exhibits the same coefficient of thermal expansion as the workpiece. This allows maximization of surface area contact between the fixture and the workpiece during the brazing operation in order to force the workpiece to maintain its design dimensions and to prevent the joint from opening. The fixture includes a cavity preventing fixture/workpiece contact in the area of the braze to help control thermal lag in the area of the joint.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: October 10, 2000
    Assignee: Allison Engine Company, Inc.
    Inventors: Raymond Ruiwen Xu, Stephen N. Hammond, Richard P. Chesnes
  • Patent number: 5102031
    Abstract: Braze filler alloy is specifically applied and metallurgically bonded to a desired region of a nickel based superalloy workpiece using an electrospark deposition technique. The braze filler alloy is deposited onto, and concurrently metallurgically alloyed into, the desired region of the base metal by transfer of the material from the electrode using a short duration electrical impulse. The time and energy involved are small enough that total heat input to the base metal is minimal so that distortion and metallurgical structure changes of the base metal are negligible.
    Type: Grant
    Filed: March 11, 1991
    Date of Patent: April 7, 1992
    Assignee: General Motors Corporation
    Inventors: Peter W. Heitman, Stephen N. Hammond, Lawrence E. Brown, Elizabeth J. Holmes
  • Patent number: 5071059
    Abstract: Single crystal, nickel based superalloy turbine blades are formed by fusion welding together two matched blade halves. The matched blade halves are joined by an electrospark deposition process which deposits a weld filler metal along the matched faying surfaces. The deposited weld filler metal is preferably the same nickel based superalloy used to form the single crystal turbine blades. Total heat input to the base metal is minimal so that distortion and metallurgical structure changes of the base metal are virtually nonexistent.
    Type: Grant
    Filed: March 11, 1991
    Date of Patent: December 10, 1991
    Assignee: General Motors Corporation
    Inventors: Peter W. Heitman, Stephen N. Hammond, Lawrence E. Brown