US3576681A - Wrought nickel base alloy article - Google Patents

Wrought nickel base alloy article Download PDF

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Publication number
US3576681A
US3576681A US810611A US3576681DA US3576681A US 3576681 A US3576681 A US 3576681A US 810611 A US810611 A US 810611A US 3576681D A US3576681D A US 3576681DA US 3576681 A US3576681 A US 3576681A
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alloy
present
solutioning
alloys
strength
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James F Barker
Eugene L Dunn
Stanley F Sternasty
Carl S Wukusick
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General Electric Co
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General Electric Co
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
    • C22C19/056—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 10% but less than 20%

Definitions

  • a wrought, ductile nickel base superalloy article allows inclusion of relatively large amounts each of the gamma prime strengtheners Al, Ti and Cb, for example in combination by weight, 3-4% Al, 2-3.5% Ti and 3-5% Cb, while maintaining improved tensile ductility and creep rupture strength through a processing procedure employing relatively low temperature solutioning, and preferably a preliminary aging prior to solutioning.
  • One type of material of significant interest has been the nickeldbase superalloy applied both as a casting alloy as well as produced as a wrought alloy article in the form of ingot, slab, bar, rod, sheet, forgings, etc. as well as in the form of engine components.
  • a principal object of the present invention is the provi-y Varticleof-aimproved--ductility andcreep rupture strength in the intermediate temperature range of about 900-l400
  • Another object is the provision of such an improved nickel-base superalloy as a forged article having high strength properties andductility in the intermediate tem-Y perature range of about 900 ⁇ 1200 F.
  • FIG. l is a graphical comparison of stress rupt-ure strength of the present invention with known alloys
  • FIG. 2 is a graphical .comparison of 0.2% yield strength data of the present invention with known alloys
  • FIG. 3 is a graphical presentation of creep data
  • FIG. 4 is a graphical presentation of tensile data and a comparison with known alloys.
  • vStrengthening mechanisms in modern high strength nickel-base superalloys generally include the precipitation strengthening and the solution strengthening types.
  • the precipitation of carbides is influential on the properties of such alloys, a more effective strengthening Patented Apr. 27, 1971 l Ce precipitate is gamma prime, Nia (Al, Ti), sometimes modied to include Cb.
  • Control of such a mechanism has allowed development of relatively high tensile and stress rupture properties at elevated temperatures.
  • the levels and relationships between such elements as Al, Ti and, when used, Cb are critical because the properties obtainable from the gamma prime strengthening precipitate can vary between wide extremes depending upon the kind of structure and phases formed.
  • solution strengthening mechanism Combined with the precipitate strengthening mechanism in a nickel-base superalloy is the solution strengthening mechanism resulting from the inclusion of a variety of vsolid solution forming elements.
  • the most commonly used elements for such purpose have been Cr, Co, Mo and W, although Cr and Co generally are added more for oxidation resistance and hot workability, respectively, than for strengthening effects.
  • Mo and W have been used as the major solution strengtheners.
  • One aspect of the present invention recognizes a particular critical relationship between the elements Al, Ti and Cb which allows their use together at higher concentrations.
  • the major strengthening mechanism in the present invention results from the combination of such elements with nickel to allow the formation of a tine generally discrete gamma prime or Nia (Al, Ti, Cb) dispersion.
  • the optimum Al/Ti ratio appears to be about 1.
  • the strength is sharply increased.
  • the gamma prime stability can be enhanced while increasing the strength of the alloy by including Cb in the range of about 3-5 weight percent with 3-4% A1 and 2-3.5% Ti.
  • the relative Al concentration must be increased to stabilize the cubic structure of Nia (Al, Ti, Cb) over the Nia ⁇ Cb or Nia Ti phases which are not effective strengtheners.
  • Cb is included in the alloy of the present invention in the range of about 3-5 weight percent. Ordinarily, a total content of Al, Ti and Cb in the range of about 8-12 weight percent would result in an alloy of low ductility.
  • the combination of elements in the present invention allows definition of a different strengthening arrangement than has heretofore been recognized, allowing the inclusion of larger amounts of ⁇ Cb in the range of about 3-5 Weight percent along with 3-4% A1 and 2-3.5% Ti.
  • the carbide forming elements included in the present invention are Ti, Cb, Cr, Mo and W.
  • Ti and Cb usually form a simple MC type carbide whereas the other carbide formers provide complex carbides of the MaaCa and MSC type carbides.
  • the complex carbides are formed at lower temperatures than are the simpler carbides and are less stable. It is believed that the complex carbides form as a result of breakdown of the simpler MC type carbides during hot working operations or during aging, or both, because of the presence oficarbon in excess of that accommodated by the MC carbide forming elements.
  • carbon should be included in the range of about 0.050.25 and preferably 0. 1-O.2%
  • a processing procedure involving the utilization of a relatively low solutioning preferably coupled with a preliminary aging prior to solution to improve tensile ductility and creep strength.
  • a processing procedure involves the utilization of a relatively low solutioning preferably coupled with a preliminary aging prior to solution to improve tensile ductility and creep strength.
  • 'I'he preferred form of such processing involves aging at about 1550- l750 F. and preferably l600-l700 F. before solutioning at about 190042100 F.
  • the alloy composition of the present invention which has been found to provide the improved combination of properties consists essentially of, by weight, 34% Al, 2-3.5% Ti, 3-5% Cb, Mo and W in an amount such that the sum of the Mo and half of the W is in the range of 4-8%, 516% Co, 9-16% Cr, 0.05-0.25% C, 0.005- 0.03% B, up to about 0.1% Zr with the balance Ni and incidental impurities.
  • the preferred form of such an alloy consists essentially of, by weight, 3-4% Al, 2-3% Ti, 3-5% Cb, 3-5% Mo, 3-5% W, 5-16% Co, 13-16% Cr, 0.1-0.2% C, Q01-0.02% B, 0.01-0.1% Zr, with the balance nickel and incidental impurities.
  • Fe in amounts more than as an impurity is detrimentalto certain mechanical properties of the alloy article and is not a substitute for any portion of lthe elements Ni and Co with which it chemically is closely related.
  • the alloy of the present invention has significantly improved properties.
  • the graphical comparison of FIG. 1 shows the average stress rupture strength of the alloy forms within the scope of the present invention, as represented by the Table I compositions, is signicantly improved over the known alloys.
  • the alloys of Table I were solutioned at the relatively low temperature of about 195 0 F. Normally, higher solution temperatures are used for alloys of this type.
  • solutioning of an alloy article which in the interpretation of the present invention is intended to include an ingot or slab, at a relatively low solutioning temperature in the range of about l900-2100 F., develops improved tensile properties in the article even though the alloy includes an unusually high combination of gamma prime strengtheners in the range of, by weight, 34% A1, 23.5% Ti, and 3-5% Cb.
  • FIG. 2 is .a graphical comparison of the 0.2% yield strength of rthe alloy form of Example '8, within the TABLE IV.-CREEP RUPTURE [1,200 F.-170,000 p.s.i.]
  • Example life hours. percent percent
  • tests at l200 F. and 150,000 p.s.i. disclosed the alloy form of Example 8 to have a creep rupture life of 512 hours compared with a life of only 8 hours for the alloy of Example 12.
  • the present invention recognizes that a wrought nickel-base superalloy including an unusually high and particular combination of the garnma prime strengtheners Al, Ti and Cb can be provided with certain improved properties through a processing procedure employing a relatively low temperature solutioning.
  • still better properties for certain uses can be developed in the present invention through a type of processing described in greater detail in co-pending and concurrently led application Ser. No. 810,612.
  • the improved processing described in that co-pending application involves the use of a preliminary aging procedure prior to solutioning.
  • the improved properties can be attained as a result of preliminary aging in the temperature range of about 1550-1750" F.
  • alloy form 8 within the scope of the present invention, has been shown to have good tensile ductility and to have significantly greater strength properties than known alloy forms, its properties can be further enhanced by particular processing.
  • the alloy of Example 8 was provided as 1A to 1% diameter bar stock prepared by rod-rolling previously extruded stock.
  • the bar stock was homogenized at 2000 F. and air cooled prior to final processing to insure relative uniformity in structure.
  • final processing of nickel base superalloys of the type to which the present invention relates involves first solutioning at a relatively high temperature prior to subsequent aging.
  • one group of specimens from the alloy of Example 8 were -frst preliminarily aged for about a day at a series of temperatures ranging from about l450-l850 F.
  • the speci- -mens were then subjected to the relatively low solutioning temperature in the range of l9002l00 F. prior to final aging.
  • a flat 1" thick forging of the alloy of Example 8 was prepared. It was preliminarily aged at about 1650 F. prior to solutioning at about 2000 F. and then aged as described above in connection with the data of FIG. 3. Typical of the significantly improved tensile properties obtained from such a forging are the data presented in graphical form in FIG. 4.
  • FIG. 4 compares the 0.2% yield strength of the present invention with that of the two known wrought nickel base superalloys as represented by the compositions of Examples 13 and 14 in Table III.
  • carbon be included in the alloy of the present invention in the proper range for the precipitation of stable carbides.
  • the presence of the proper type and the amount of canbides is significant in grain size control in subsequent processing. Addition of carbon up to about 0.05% functions as a deoxidizer.
  • zirconium is added in part for deoxidizing purposes. However, retention of amounts up to about 0.1% assists in the provision of higher creep rupture ductility.
  • Cobalt is included in the alloy of the present invention for ythe ⁇ double purpose of improving workability and as a solution strengthener. However, it is recognized that it also may stabilize the gamma prime.
  • Cr is required in the matrix to allow the formation of the super-saturated solution with the amounts of Al, Ti and Cb hardeners in the alloy. Thus it affects the solubility of the gamma prime hardeners. Cr is required in amounts of at least about 9 weight percent to assist in the precipitation of substantial amounts of gamma prime.
  • Fe does not improve strength properties and is, in fact, detrimental to certain strength properties at temperatures above about l000 F. Too much Fe results in the formation of excessive mu and other detrimental intermetallic phases. In addition, it results in low temperature brittleness and low strength at high temperatures.
  • a wrought nickel base alloy article of improved tensile ductility and creep properties as a result of solutioning in the range of 1900-2l00 F., the alloy of the article consisting essentially of, by weight: 3-4% Al, 2- 3.5% Ti, 3-5% Cb, Mo and W in an amount such that the total of Mo and half of the W is in the range of 4- 8%, 5-16% Co, 9-l6% Cr, 0.050.25% C, 0.0050.03% B, up to about 0.1% Zr with the balance nickel and incidental impurities.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Conductive Materials (AREA)
  • Manufacture And Refinement Of Metals (AREA)
US810611A 1969-03-26 1969-03-26 Wrought nickel base alloy article Expired - Lifetime US3576681A (en)

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US (1) US3576681A (de)
BE (1) BE743402A (de)
CH (1) CH552675A (de)
DE (1) DE1964992C3 (de)
FR (1) FR2033709A5 (de)
GB (1) GB1263827A (de)
NL (1) NL6919328A (de)
SE (1) SE421633B (de)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3768147A (en) * 1971-12-20 1973-10-30 Gen Electric Method of friction welding
US3916497A (en) * 1973-02-16 1975-11-04 Mitsubishi Metal Corp Heat resistant and wear resistant alloy
US3917463A (en) * 1973-02-16 1975-11-04 Mitsubishi Metal Corp Nickel-base heat resistant and wear resistant alloy
US3957450A (en) * 1973-01-15 1976-05-18 General Electric Company Article of manufacture with pre-determined fatigue life
US4530727A (en) * 1982-02-24 1985-07-23 The United States Of America As Represented By The Department Of Energy Method for fabricating wrought components for high-temperature gas-cooled reactors and product
DE3525080A1 (de) * 1984-07-23 1986-01-23 General Electric Co., Schenectady, N.Y. Verfahren und elektroplattierband zum aufbringen von schleifteilchen auf eine oberflaeche
US4685977A (en) * 1984-12-03 1987-08-11 General Electric Company Fatigue-resistant nickel-base superalloys and method
US4957567A (en) * 1988-12-13 1990-09-18 General Electric Company Fatigue crack growth resistant nickel-base article and alloy and method for making
US5143563A (en) * 1989-10-04 1992-09-01 General Electric Company Creep, stress rupture and hold-time fatigue crack resistant alloys
DE4412031A1 (de) * 1993-04-07 1994-10-13 Aluminum Co Of America Verfahren zur Herstellung von Schmiedeteilen aus Nickellegierungen
US5374323A (en) * 1991-08-26 1994-12-20 Aluminum Company Of America Nickel base alloy forged parts
US5413752A (en) * 1992-10-07 1995-05-09 General Electric Company Method for making fatigue crack growth-resistant nickel-base article
US5725692A (en) * 1995-10-02 1998-03-10 United Technologies Corporation Nickel base superalloy articles with improved resistance to crack propagation
US5820700A (en) * 1993-06-10 1998-10-13 United Technologies Corporation Nickel base superalloy columnar grain and equiaxed materials with improved performance in hydrogen and air
US20100303665A1 (en) * 2009-05-29 2010-12-02 General Electric Company Nickel-base superalloys and components formed thereof
US20100303666A1 (en) * 2009-05-29 2010-12-02 General Electric Company Nickel-base superalloys and components formed thereof
US20120084980A1 (en) * 2010-10-12 2012-04-12 Alstom Technology Ltd. Extending Useful Life of a Cobalt-Based Gas Turbine Component
EP2520395A2 (de) 2011-05-04 2012-11-07 General Electric Company Komponenten und Verfahren zur Herstellung von Komponenten mit Regionen mit unterschiedlicher Kornstruktur
EP2530181A1 (de) 2011-06-03 2012-12-05 General Electric Company Komponenten und Verfahren zur Herstellung von Komponenten mit Regionen mit unterschiedlicher Kornstruktur

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2455488C2 (de) * 1974-11-23 1983-03-31 Stabilus Gmbh, 5400 Koblenz Ausstellvorrichtung für nach oben zu öffnende, schwenkbare Klappen
DE2513302C2 (de) * 1975-03-26 1985-05-30 Stabilus Gmbh, 5400 Koblenz Blockierbare pneumatische oder hydropneumatische Feder
DE2653552C2 (de) * 1976-11-25 1982-06-09 Fritz Bauer + Söhne oHG, 8503 Altdorf Gasfeder, die als Hubhilfe für das Öffnen und zum Halten von Heckklappen oder Kofferraumdeckeln von Kraftfahrzeugen in der Öffnungsstellung ausgebildet ist
DE3030408C2 (de) * 1980-08-12 1986-03-06 Boge Gmbh, 5208 Eitorf Verstell- und Dämpfungsvorrichtung, insbesondere für verstellbare Sitzmöbel bzw. Sitzmöbelteile
DE3337297C2 (de) * 1983-10-13 1985-08-29 Liebherr-Hydraulikbagger Gmbh, 7951 Kirchdorf Ausstellvorrichtung für ein Frontfenster eines Fahrzeuges oder Führerhauses mit ausstellbarer Scheibe
FR2555205B1 (fr) * 1983-11-22 1989-05-19 Metalimphy Alliages a base de nickel pour la metallurgie des poudres destines a des disques de turbines a gaz
DE3413781A1 (de) * 1984-04-12 1985-10-24 Hermann Dipl.-Ing. Bansbach (FH), 7073 Lorch Verstellbare stuetze
US4629521A (en) * 1984-12-10 1986-12-16 Special Metals Corporation Nickel base alloy
DE3615648A1 (de) * 1985-07-19 1987-01-29 Hermann Bansbach Vorrichtung mit einem in einem zylindermantel bewegbaren kolben
US4888064A (en) * 1986-09-15 1989-12-19 General Electric Company Method of forming strong fatigue crack resistant nickel base superalloy and product formed
DE3933360A1 (de) * 1989-10-06 1991-04-18 Stabilus Gmbh Ausloesestift fuer ein stufenlos blockierbares hubaggregat, mit integriertem ueberdruckventil
NL9001634A (nl) * 1990-07-18 1992-02-17 Imasaco Ag Instelbare kolom.
DE4127917C2 (de) * 1991-08-23 2000-01-20 Stabilus Gmbh Federungseinrichtung
DE19548139C2 (de) * 1995-12-21 1998-09-24 Stabilus Gmbh Gasfeder mit einstellbarer Endposition
DE29617609U1 (de) * 1996-10-10 1996-12-19 Krautheim, Harald, 34399 Oberweser Hubgestell für einen höhenverstellbaren Tisch

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3768147A (en) * 1971-12-20 1973-10-30 Gen Electric Method of friction welding
US3957450A (en) * 1973-01-15 1976-05-18 General Electric Company Article of manufacture with pre-determined fatigue life
US3916497A (en) * 1973-02-16 1975-11-04 Mitsubishi Metal Corp Heat resistant and wear resistant alloy
US3917463A (en) * 1973-02-16 1975-11-04 Mitsubishi Metal Corp Nickel-base heat resistant and wear resistant alloy
US4530727A (en) * 1982-02-24 1985-07-23 The United States Of America As Represented By The Department Of Energy Method for fabricating wrought components for high-temperature gas-cooled reactors and product
DE3525080A1 (de) * 1984-07-23 1986-01-23 General Electric Co., Schenectady, N.Y. Verfahren und elektroplattierband zum aufbringen von schleifteilchen auf eine oberflaeche
US4685977A (en) * 1984-12-03 1987-08-11 General Electric Company Fatigue-resistant nickel-base superalloys and method
US4957567A (en) * 1988-12-13 1990-09-18 General Electric Company Fatigue crack growth resistant nickel-base article and alloy and method for making
US5143563A (en) * 1989-10-04 1992-09-01 General Electric Company Creep, stress rupture and hold-time fatigue crack resistant alloys
US5374323A (en) * 1991-08-26 1994-12-20 Aluminum Company Of America Nickel base alloy forged parts
US5360496A (en) * 1991-08-26 1994-11-01 Aluminum Company Of America Nickel base alloy forged parts
US5413752A (en) * 1992-10-07 1995-05-09 General Electric Company Method for making fatigue crack growth-resistant nickel-base article
DE4412031A1 (de) * 1993-04-07 1994-10-13 Aluminum Co Of America Verfahren zur Herstellung von Schmiedeteilen aus Nickellegierungen
US5820700A (en) * 1993-06-10 1998-10-13 United Technologies Corporation Nickel base superalloy columnar grain and equiaxed materials with improved performance in hydrogen and air
US5725692A (en) * 1995-10-02 1998-03-10 United Technologies Corporation Nickel base superalloy articles with improved resistance to crack propagation
US5788785A (en) * 1995-10-02 1998-08-04 United Technology Corporation Method for making a nickel base alloy having improved resistance to hydrogen embittlement
US8992700B2 (en) 2009-05-29 2015-03-31 General Electric Company Nickel-base superalloys and components formed thereof
US20100303665A1 (en) * 2009-05-29 2010-12-02 General Electric Company Nickel-base superalloys and components formed thereof
US20100303666A1 (en) * 2009-05-29 2010-12-02 General Electric Company Nickel-base superalloys and components formed thereof
US9518310B2 (en) 2009-05-29 2016-12-13 General Electric Company Superalloys and components formed thereof
US8992699B2 (en) 2009-05-29 2015-03-31 General Electric Company Nickel-base superalloys and components formed thereof
US20120084980A1 (en) * 2010-10-12 2012-04-12 Alstom Technology Ltd. Extending Useful Life of a Cobalt-Based Gas Turbine Component
US9056372B2 (en) * 2010-10-12 2015-06-16 Alstom Technology Ltd Extending useful life of a cobalt-based gas turbine component
US8918996B2 (en) 2011-05-04 2014-12-30 General Electric Company Components and processes of producing components with regions having different grain structures
EP2520395A2 (de) 2011-05-04 2012-11-07 General Electric Company Komponenten und Verfahren zur Herstellung von Komponenten mit Regionen mit unterschiedlicher Kornstruktur
EP2530181A1 (de) 2011-06-03 2012-12-05 General Electric Company Komponenten und Verfahren zur Herstellung von Komponenten mit Regionen mit unterschiedlicher Kornstruktur
US9156113B2 (en) 2011-06-03 2015-10-13 General Electric Company Components and processes of producing components with regions having different grain structures

Also Published As

Publication number Publication date
DE1964992C3 (de) 1978-03-02
SE421633B (sv) 1982-01-18
BE743402A (de) 1970-05-28
DE1964992A1 (de) 1970-10-01
NL6919328A (de) 1970-09-29
CH552675A (de) 1974-08-15
DE1964992B2 (de) 1977-07-07
GB1263827A (en) 1972-02-16
FR2033709A5 (de) 1970-12-04

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