Patents by Inventor David S. Bergstrom

David S. Bergstrom 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: 8387228
    Abstract: A method for producing a single-clad or multiple-clad product includes providing a welded assembly comprising a cladding material disposed on a substrate material. Both the substrate material and the cladding material are individually selected alloys. At least a first edge of the cladding material of the welded assembly does not extend to a first edge of the substrate material and thereby provides a margin between the first edges. A material that is an alloy having hot strength greater than the cladding material is within the margin and adjacent the first edge of the cladding material. The welded assembly is hot rolled to provide a hot rolled band, and the material within the margin inhibits the cladding material from spreading beyond the edge of the substrate material during the hot rolling. In certain embodiments of the methods, the substrate material is stainless steel and the cladding material is nickel or a nickel alloy.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: March 5, 2013
    Assignee: ATI Properties, Inc.
    Inventors: David S. Bergstrom, Kris J. Schott, Mark A. Tarhay
  • Patent number: 8337749
    Abstract: An austenitic stainless steel composition including relatively low Ni and Mo levels, and exhibiting corrosion resistance, resistance to elevated temperature deformation, and formability properties comparable to certain alloys including higher Ni and Mo levels. Embodiments of the austenitic stainless steel include, in weight percentages, up to 0.20 C, 2.0-9.0 Mn, up to 2.0 Si, 15.0-23.0 Cr, 1.0-9.5 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.05-0.35 N, (7.5(% C))?(% Nb+% Ti+% V+% Ta+% Zr)?1.5, Fe, and incidental impurities.
    Type: Grant
    Filed: November 2, 2009
    Date of Patent: December 25, 2012
    Assignee: ATI Properties, Inc.
    Inventors: David S. Bergstrom, James M. Rakowski
  • Patent number: 8337748
    Abstract: An austenitic stainless steel composition including relatively low nickel and molybdenum levels, and exhibiting corrosion resistance, resistance to elevated temperature deformation, and formability properties comparable to certain alloys including higher nickel and molybdenum levels. Embodiments of the austenitic stainless steel include, in weight %, up to 0.20 C, 2.0-9.0 Mn, up to 2.0 Si, 16.0-23.0 Cr, 1.0-7.0 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.05-0.35 N, up to 4.0 W, (7.5(% C))?(Nb+Ti+V+Ta+Zr)?1.5, up to 0.01 B, up to 1.0 Co, iron and impurities. Additionally, embodiments of the steel may include 0.5?(Mo+W/2)?5.0 and/or 1.0?(Ni+Co)?8.0.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: December 25, 2012
    Assignee: ATI Properties, Inc.
    Inventors: James M. Rakowski, David S. Bergstrom, Charles P. Stinner, John J. Dunn, John F. Grubb
  • Patent number: 8313691
    Abstract: An austenitic stainless steel having low nickel and molybdenum and exhibiting comparable corrosion resistance and formability properties to higher nickel and molybdenum alloys comprises, in weight %, up to 0.20 C, 2.0-9.0 Mn, up to 2.0 Si, 16.0-23.0 Cr, 1.0-5.0 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.1-0.35 N, up to 4.0 W, up to 0.01 B, up to 1.0 Co, iron and impurities, the steel having a ferrite number of less than 10 and a MD30 value of less than 20° C.
    Type: Grant
    Filed: February 26, 2008
    Date of Patent: November 20, 2012
    Assignee: ATI Properties, Inc.
    Inventors: David S. Bergstrom, James M. Rakowski, Charles P. Stinner, John J. Dunn, John F. Grubb
  • Publication number: 20100047105
    Abstract: An austenitic stainless steel composition including relatively low Ni and Mo levels, and exhibiting corrosion resistance, resistance to elevated temperature deformation, and formability properties comparable to certain alloys including higher Ni and Mo levels. Embodiments of the austenitic stainless steel include, in weight percentages, up to 0.20 C, 2.0-9.0 Mn, up to 2.0 Si, 15.0-23.0 Cr, 1.0-9.5 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.05-0.35 N, (7.5(% C))?(%Nb+%Ti+%V+%Ta+%Zr)?1.5, Fe, and incidental impurities.
    Type: Application
    Filed: November 2, 2009
    Publication date: February 25, 2010
    Applicant: ATI Properties, Inc.
    Inventors: David S. Bergstrom, James M. Rakowski
  • Publication number: 20090162237
    Abstract: An austenitic stainless steel composition including relatively low nickel and molybdenum levels, and exhibiting corrosion resistance, resistance to elevated temperature deformation, and formability properties comparable to certain alloys including higher nickel and molybdenum levels. Embodiments of the austenitic stainless steel include, in weight %, up to 0.20 C, 2.0-9.0 Mn, up to 2.0 Si, 16.0-23.0 Cr, 1.0-7.0 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.05-0.35 N, up to 4.0 W, (7.5(% C))?(Nb+Ti+V+Ta+Zr)?1.5, up to 0.01 B, up to 1.0 Co, iron and impurities. Additionally, embodiments of the steel may include 0.5?(Mo+W/2)?5.0 and/or 1.0?(Ni+Co)?8.0.
    Type: Application
    Filed: February 20, 2008
    Publication date: June 25, 2009
    Applicant: ATI Properties, Inc.
    Inventors: James M. Rakowski, David S. Bergstrom, Charles P. Stinner, John J. Dunn, John F. Grubb
  • Publication number: 20090162238
    Abstract: An austenitic stainless steel composition having low nickel and molybdenum and exhibiting high corrosion resistance and good formability. The austenitic stainless steel includes, in weight %, up to 0.20 C, 2.0-6.0 Mn, up to 2.0 Si, 16.0-23.0 Cr, 5.0-7.0 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.1-0.35 N, up to 4.0 W, up to 0.01 B, up to 1.0 Co, iron and impurities. The austenitic stainless steel has a ferrite number less than 11 and an MD30 value less than ?10° C.
    Type: Application
    Filed: February 26, 2008
    Publication date: June 25, 2009
    Applicant: ATI Properties, Inc.
    Inventors: David S. Bergstrom, James M. Rakowski, Charles P. Stinner, John J. Dunn, John F. Grubb
  • Publication number: 20090142218
    Abstract: An austenitic stainless steel having low nickel and molybdenum and exhibiting comparable corrosion resistance and formability properties to higher nickel and molybdenum alloys comprises, in weight %, up to 0.20 C, 2.0-9.0 Mn, up to 2.0 Si, 16.0-23.0 Cr, 1.0-5.0 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.1-0.35 N, up to 4.0 W, up to 0.01 B, up to 1.0 Co, iron and impurities, the steel having a ferrite number of less than 10 and a MD30 value of less than 20° C.
    Type: Application
    Filed: February 26, 2008
    Publication date: June 4, 2009
    Applicant: ATI Properties, Inc.
    Inventors: David S. Bergstrom, James M. Rakowski, Charles P. Stinner, John J. Dunn, John F. Grubb
  • Patent number: 6623569
    Abstract: A duplex stainless steel includes less than, in weight percent, 3 percent nickel and 1.5 percent molybdenum. In one embodiment, the duplex stainless steel includes, in weight percent, up to 0.06 percent carbon; 15 to 25 percent chromium; 1 to less than 2.5 percent nickel; greater than 2 percent up to 3.75 percent manganese; greater than 0.12 up to 0.35 percent nitrogen; up to 2 percent silicon; up to 1.5 percent molybdenum; up to 0.5 percent copper; up to 0.2 percent cobalt; up to 0.05 percent phosphorous; up to 0.005 percent sulfur; 0.001 to 0.0035 percent boron; iron and incidental impurities. The duplex stainless steel provided may be provided in the form of an article of manufacture, such as strip, bar, plate, sheet, casting, tubing or piping. A method for making the duplex stainless steel of the invention also is disclosed.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: September 23, 2003
    Assignee: ATI Properties, Inc.
    Inventors: David S. Bergstrom, John J. Dunn, John F. Grubb, William A. Pratt
  • Publication number: 20030084971
    Abstract: A duplex stainless steel includes less than, in weight percent, 3 percent nickel and 1.5 percent molybdenum. In one embodiment, the duplex stainless steel includes, in weight percent, up to 0.06 percent carbon; 15 to 25 percent chromium; 1 to less than 2.5 percent nickel; greater than 2 percent up to 3.75 percent manganese; greater than 0.12 up to 0.35 percent nitrogen; up to 2 percent silicon; up to 1.5 percent molybdenum; up to 0.5 percent copper; up to 0.2 percent cobalt; up to 0.05 percent phosphorous; up to 0.005 percent sulfur; 0.001 to 0.0035 percent boron; iron and incidental impurities. The duplex stainless steel provided may be provided in the form of an article of manufacture, such as strip, bar, plate, sheet, casting, tubing or piping. A method for making the duplex stainless steel of the invention also is disclosed.
    Type: Application
    Filed: September 10, 2002
    Publication date: May 8, 2003
    Inventors: David S. Bergstrom, John J. Dunn, John F. Grubb, William A. Pratt
  • Patent number: 6551420
    Abstract: A duplex stainless steel including, in weight percent, up to 0.06 percent carbon, 15 up to less than 25 percent chromium, greater than 3 up to 6 percent nickel, up to 3.75 percent manganese, 0.14 up to 0.35 percent nitrogen, up to 2 percent silicon, greater than 1.4 up to less than 2.5 percent molybdenum, up to less than 0.5 percent copper, up to less than 0.2 percent cobalt, up to 0.05 percent phosphorous, up to 0.005 percent sulfur, and 0.001 up to 0.0035 percent boron, with the remainder being iron and incidental impurities is disclosed. The duplex stainless steel may be included in an article of manufacture, such as a strip, bar, plate, sheet, casting, tubing or piping. A method for making such a duplex stainless steel is also disclosed.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: April 22, 2003
    Assignee: ATI Properties, Inc.
    Inventors: David S. Bergstrom, John J. Dunn, John F. Grubb, William A. Pratt
  • Patent number: 6273973
    Abstract: A process for producing a steel includes subjecting at least a portion of a melt of the steel to electroslag remelting and, in a subsequent step, heating the steel to a temperature at least as great as the lowest temperature at which all carbides that can form in the remelted steel will dissolve and no greater than the nil ductility temperature of the of the remelted steel, and maintaining the temperature for a period of time sufficient to dissolve primary and clustered carbide particles in the remelted steel greater than 15 micrometers in length. A novel martensitic stainless steel also is disclosed including 0.65 to 0.70 carbon; 0 to 0.025 phosphorus; 0 to 0.020 sulfur; 0.20 to 0.50 silicon; at least one of greater than 0.0004 boron and greater than 0.03 nitrogen; 0.45 to 0.75 manganese; 12.7 to 13.7 chromium; and 0 to 0.50 nickel.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: August 14, 2001
    Assignee: ATI Properties, Inc.
    Inventors: Thomas R. Parayil, David S. Bergstrom, Raymond A. Painter