Patents by Inventor S. Krishna Srivastava

S. Krishna Srivastava 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: 10577680
    Abstract: Ni—Cr—Co—Mo—Al based alloys are disclosed which contain 15 to 20 wt. % chromium, 9.5 to 20 wt. % cobalt, 7.25 to 10 wt. % molybdenum, 2.72 to 3.89 wt. % aluminum, certain minor elemental additions, along with typical impurities, a tolerance for up to 10.5 wt. % iron, and a balance of nickel. These alloys are readily fabricable, have high creep strength, good thermal stability, and excellent oxidation resistance up to as high as 2100° F. (1149° C.). This combination of properties is useful for a variety of gas turbine engine components, including, for example, combustors.
    Type: Grant
    Filed: June 27, 2019
    Date of Patent: March 3, 2020
    Assignee: Haynes International, Inc.
    Inventors: S. Krishna Srivastava, Lee Pike
  • Publication number: 20190323107
    Abstract: Ni—Cr—Co—Mo—Al based alloys are disclosed which contain 15 to 20 wt. % chromium, 9.5 to 20 wt. % cobalt, 7.25 to 10 wt. % molybdenum, 2.72 to 3.89 wt. % aluminum, certain minor elemental additions, along with typical impurities, a tolerance for up to 10.5 wt. % iron, and a balance of nickel. These alloys are readily fabricable, have high creep strength, good thermal stability, and excellent oxidation resistance up to as high as 2100° F. (1149° C.). This combination of properties is useful for a variety of gas turbine engine components, including, for example, combustors.
    Type: Application
    Filed: June 27, 2019
    Publication date: October 24, 2019
    Inventors: S. Krishna Srivastava, Lee Pike
  • Patent number: 10358699
    Abstract: Ni—Cr—Co—Mo—Al based alloys are disclosed which contain 15 to 20 wt. % chromium, 9.5 to 20 wt. % cobalt, 7.25 to 10 wt. % molybdenum, 2.72 to 3.89 wt. % aluminum, certain minor elemental additions, along with typical impurities, a tolerance for up to 10.5 wt. % iron, and a balance of nickel. These alloys are readily fabricable, have high creep strength, and excellent oxidation resistance up to as high as 2100° F. (1149° C.). This combination of properties is useful for a variety of gas turbine engine components, including, for example, combustors.
    Type: Grant
    Filed: April 18, 2018
    Date of Patent: July 23, 2019
    Assignee: Haynes International, Inc.
    Inventors: S. Krishna Srivastava, Lee Pike
  • Publication number: 20180230578
    Abstract: Ni—Cr—Co—Mo—Al based alloys are disclosed which contain 15 to 20 wt. % chromium, 9.5 to 20 wt. % cobalt, 7.25 to 10 wt. % molybdenum, 2.72 to 3.89 wt. % aluminum, certain minor elemental additions, along with typical impurities, a tolerance for up to 10.5 wt. % iron, and a balance of nickel. These alloys are readily fabricable, have high creep strength, and excellent oxidation resistance up to as high as 2100° F. (1149° C.). This combination of properties is useful for a variety of gas turbine engine components, including, for example, combustors.
    Type: Application
    Filed: April 18, 2018
    Publication date: August 16, 2018
    Inventors: S. Krishna Srivastava, Lee Pike
  • Publication number: 20160002752
    Abstract: Ni—Cr—Co—Mo—Al based alloys are disclosed which contain 15 to 20 wt. % chromium, 9.5 to 20 wt. % cobalt, 7.25 to 10 wt. % molybdenum, 2.72 to 3.9 wt. % aluminum, along with typical impurities, a tolerance for up to 10.5 wt. % iron, minor element additions and a balance of nickel. These alloys are readily fabricable, have high creep strength, and excellent oxidation resistance up to as high as 2100° F. (1149° C.). This combination of properties is useful for a variety of gas turbine engine components, including, for example, combustors.
    Type: Application
    Filed: March 14, 2014
    Publication date: January 7, 2016
    Inventors: S. Krishna Srivastava, Lee Pike
  • Patent number: 8545643
    Abstract: An alloy designed for use in gas turbine engines which has high strength and a low coefficient of thermal expansion is disclosed. The alloy may contain in weight percent 7% to 9% chromium, 21% to 24% molybdenum, greater than 5% tungsten, up to 3% iron, with a balance being nickel and impurities. The alloy must further satisfy the following compositional relationship: 31.95<R<33.45, where the R value is defined by the equation: R=2.66Al+0.19Co+0.84Cr?0.16Cu+0.39Fe+0.60Mn+Mo+0.69Nb+2.16Si+0.47Ta+1.36Ti+1.07V+0.40W The alloy has better hardness after being age-hardened at 1400° F. (760° C.) if tungsten is present from greater than 5% up to 10% and a preferred density if the alloy contains greater than 5% up to 7% tungsten.
    Type: Grant
    Filed: February 17, 2012
    Date of Patent: October 1, 2013
    Assignee: Haynes International, Inc.
    Inventors: Lee Pike, S. Krishna Srivastava
  • Publication number: 20120213660
    Abstract: An alloy designed for use in gas turbine engines which has high strength and a low coefficient of thermal expansion is disclosed. The alloy may contain in weight percent 7% to 9% chromium, 21% to 24% molybdenum, greater than 5% tungsten, up to 3% iron, with a balance being nickel and impurities. The alloy must further satisfy the following compositional relationship: 31.95<R<33.45, where the R value is defined by the equation: R=2.66Al+0.19Co+0.84Cr?0.16Cu+0.39Fe+0.60Mn+Mo+0.69Nb+2.16Si+0.47Ta+1.36Ti+1.07V+0.40W The alloy has better hardness after being age-hardened at 1400° F. (760° C.) if tungsten is present from greater than 5% up to 10% and a preferred density if the alloy contains greater than 5% up to 7% tungsten.
    Type: Application
    Filed: February 17, 2012
    Publication date: August 23, 2012
    Applicant: HAYNES INTERNATIONAL, INC.
    Inventors: Lee Pike, S. Krishna Srivastava
  • Patent number: 8075839
    Abstract: A wroughtable, cobalt alloy capable of through thickness nitridation and strengthening using practical treatments and practical sheet thicknesses contains in weight percent about 23 to about 30% chromium, about 15 to about 25% iron, up to about 27.3% nickel, about 0.75 to about 1.7% titanium, about 0.85 to about 1.9% niobium or zirconium, up to 0.2% carbon, up to 0.015% boron, up to 0.015% rare earth elements, up to 0.5% aluminum, up to 1% manganese, up to 1% silicon, up to 1% tungsten, up to 1% molybdenum, and the balance cobalt plus impurities and the total weight percent of titanium plus niobium or equivalents is from about 1.6 to about 3.6.
    Type: Grant
    Filed: September 15, 2006
    Date of Patent: December 13, 2011
    Assignee: Haynes International, Inc.
    Inventor: S. Krishna Srivastava
  • Publication number: 20080066831
    Abstract: A wroughtable, cobalt alloy capable of through thickness nitridation and strengthening using practical treatments and practical sheet thicknesses contains in weight percent about 23 to about 30% chromium, about 15 to about 25% iron, up to about 27.3% nickel, about 0.75 to about 1.7% titanium, about 0.85 to about 1.9% niobium or zirconium, up to 0.2% carbon, up to 0.015% boron, up to 0.015% rare earth elements, up to 0.5% aluminum, up to 1% manganese, up to 1% silicon, up to 1% tungsten, up to 1% molybdenum, and the balance cobalt plus impurities and the total weight percent of titanium plus niobium or equivalents is from about 1.6 to about 3.6.
    Type: Application
    Filed: September 15, 2006
    Publication date: March 20, 2008
    Inventor: S. Krishna Srivastava