EP0683239A1 - Superalliage à base de nickel résistant à l'oxydation - Google Patents

Superalliage à base de nickel résistant à l'oxydation Download PDF

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Publication number
EP0683239A1
EP0683239A1 EP94303644A EP94303644A EP0683239A1 EP 0683239 A1 EP0683239 A1 EP 0683239A1 EP 94303644 A EP94303644 A EP 94303644A EP 94303644 A EP94303644 A EP 94303644A EP 0683239 A1 EP0683239 A1 EP 0683239A1
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EP
European Patent Office
Prior art keywords
superalloy
weight percent
alloy
nickel
weight
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP94303644A
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German (de)
English (en)
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EP0683239B1 (fr
Inventor
William J. Gostic
Paul P. Norris Jr.
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Raytheon Technologies Corp
Original Assignee
United Technologies Corp
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Filing date
Publication date
Application filed by United Technologies Corp filed Critical United Technologies Corp
Priority to DE1994616110 priority Critical patent/DE69416110T2/de
Priority to EP94303644A priority patent/EP0683239B1/fr
Priority to JP12211394A priority patent/JP3474634B2/ja
Publication of EP0683239A1 publication Critical patent/EP0683239A1/fr
Application granted granted Critical
Publication of EP0683239B1 publication Critical patent/EP0683239B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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%
    • 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
    • C22C19/057—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being less 10%

Definitions

  • the present invention relates to nickel superalloys and methods for making nickel superalloys having high oxidation resistance and containing controlled amounts of boron and zirconium.
  • Such nickel superalloys are suitable for use in articles requiring good strength and superior oxidation resistance at high temperatures, including jet engine combustors, nozzles, and low turbine components.
  • a variety of nickel based superalloys are known in the art.
  • Superalloys are those alloys which maintain high strength at high temperatures. Examples of nickel based superalloys can be found in U.S. Patent Nos. 3,322,543 (Shaw et al.), 3,526,499 (Quigg et al.), 3,653,987 (Boesch), 3,667,938 (Boesch), 3,832,167 (Shaw et al.), and 4,719,080 (Duhl et al.).
  • nickel based superalloys include B1900+Hf and Mar-M 247, the nominal compositions of which are, in weight percent, B-l900+HF Mar-M-247 Nickel Balance Balance Chromium 8.0 8.4 Cobalt 10.0 10.0 Carbon 0.11 0.15 Titanium 1.0 1.1 Aluminum 6.0 5.5 Molybdenum 6.0 0.65 Tungsten - 10.0 Boron 0.015 0.015 Hafnium 1.15 1.4 Tantalum 4.25 3.1 Zirconium 0.08 0.055 Due to their ability to maintain good mechanical strength at high temperatures, these alloys are especially useful as a material for making components of jet engines.
  • Boron is typically added in the range of 0.010 to 0.020 weight percent to conventionally cast superalloys for the enhancement of grain boundary strength and ductility.
  • Zirconium is typically added in the range of 0.03 to 0.13 weight percent for further grain boundary property enhancement.
  • Yttrium can be added to nickel superalloys to enhance their oxidation resistance.
  • the nickel superalloys of the prior art which demonstrate excellent oxidation resistance at high temperature are too brittle.
  • nickel superalloys which have excellent oxidation resistance at high temperatures while at the same time possessing good ductility.
  • turbine components in jet engines which have good strength and excellent oxidation resistance within the temperature range of 760°C (14000F) to 1038°C (19000F).
  • nickel based superalloys which have excellent oxidation resistance at high temperatures and also have good ductility.
  • a polycrystalline nickel based superalloy having between about 0.25 to 0.40 weight percent zirconium and about 0.004 to 0.010 weight percent boron.
  • the alloys of the present invention have demonstrated excellent oxidation resistance up to 1093°C (2000°F), and in preferable instances up to 1204°C (2200°F).
  • the nickel superalloys of the present invention have demonstrated good strength within the temperature range of 760°C (14000F) to 1038°C (19000F).
  • the excellent oxidation resistance of the superalloys of the present invention makes them suitable for use in high temperature applications such as in a jet engine combustor, nozzle and low turbine components.
  • superalloys of the present invention contain between 5.0 and 8.0 weight percent aluminum in order to form an effective barrier layer which impedes oxidation of the superalloy. Having zirconium present in the superalloy promotes formation of the alumina barrier layer.
  • Burner rig oxidation testing revealed the detrimental effect of boron on high temperature (1093°C-1204°C (2000-2200°F)) oxidation resistance. Removing boron from the nickel superalloy solved the oxidation problem, but the resulting alloy had unacceptable ductility. Adding low levels of boron (0.002 to 0.010 weight percent) provided acceptable oxidation behavior, but ductility was marginal at best. The addition of yttrium also presented embrittlement problems due to the formation of surface oxide particles during casting, which result from the reaction between yttrium and the casting ceramics. Through further experimentation, it was discovered that the combination of zirconium and boron at the levels designated in this specification can greatly enhance the oxidation resistance of conventionally cast nickel superalloys, while maintaining grain boundary properties and avoiding inclusion formation during casting.
  • the nickel superalloy of the present invention has been found to work when elements are added in the following weight percentages: Element Percentage Chromium 5.0 - 12.0 Hafnium 0.75 - 2.0 Cobalt O - 10.0
  • alloy elements can be added for alloy strengthening: Element Percentage Tungsten 0 - 12 Molybdenum 0 - 12 Tantalum 0 - 12 Titanium 0 - 2 Columbium (Niobium) 0 - 2 Carbon 0.06 - 0.20
  • the elements manganese, phosphorus, sulfur, silicon, iron, bismuth, lead, selenium, tellurium, and thallium are preferably controlled to low levels in order to prevent degradation to the properties of the superalloy.
  • the superalloy is comprised of the following elements given in weight percentages: Element Percentage min max Carbon 0.08 - 0.13 Chromium 9.50 - 10.50 Molybdenum 1.75 - 2.25 Tungsten 3.00 - 3.40 Aluminum 6.50 - 6.70 Tantalum 3.90 - 4.30 Hafnium 1.05 - 1.25 Boron 0.004 - 0.010 zirconium 0.25 - 0.35 Nickel remainder1 1 Essentially the balance of the superalloy
  • the superalloy of the present invention may contain additive materials, such as the following, up to the indicated percent by weight maximum amounts: manganese (0.20), phosphorus (0.015), sulfur (0.015), silicon (0.10), iron (0.25), titanium (0.10), columbium (0.10), bismuth (0.00005, 0.5 ppm), lead (0.0002, 2 ppm), selenium (0.0001, 1 ppm), tellurium (0.00005, 0.5 ppm), and thallium (0.00005, 0.5 ppm).
  • additive materials such as the following, up to the indicated percent by weight maximum amounts: manganese (0.20), phosphorus (0.015), sulfur (0.015), silicon (0.10), iron (0.25), titanium (0.10), columbium (0.10), bismuth (0.00005, 0.5 ppm), lead (0.0002, 2 ppm), selenium (0.0001, 1 ppm), tellurium (0.00005, 0.5 ppm), and thallium (0.00005, 0.5 ppm).
  • articles are fabricated by taking an ingot of the requisite composition, which has been cast from a single furnace charge under vacuum, and vacuum remelting and recasting using investment casting procedures that are conventionally used for nickel based alloys.
  • Conventional investment casting procedures for superalloys, procedures for forming ingots of superalloys, and other general information regarding superalloys can be found in Superalloys II , Sims et al., eds., John Wiley & Sons, New York, 1987.
  • alloying elements in their commercially pure form are added to the master heat during ingot formation.
  • the alloying elements contain less than maximum ("max") specified amounts of the following additive materials set forth above: Mn, P, S, Si, Fe, Ti, Cb (Nb), Bi, Pb, Se, Te, and T1.
  • a nickel superalloy was made having the composition shown in Table I.
  • the invention showed superior ductility compared to a compositionally similar nickel alloy whose boron and zirconium content falls outside the critical range defined in the present invention as demonstrated below in Table II.
  • Table II Tensile Elongation (percent) Alloy Temperature 24°C (75°F) 644°C (1200°F) 871°C (1600°F) 982°C (1800°F) Invention 6.0 5.3 6.6 7.0 Alloy 1 1.3 0.7 3.3 2.0
  • superalloys of the present invention have a mean tensile elongation of three ASTM E 8 tests at 649°C (12000F) exceeding 3.0%. In a preferred embodiment, mean tensile elongation of three ASTM E 8 tests at 649°F (12000F) exceeds 5.0%.
  • Burner rig oxidation testing demonstrated that the alloy of the present invention had superior oxidation resistance compared to the conventional nickel superalloys Bl900+HF and Mar-M-247 (see Table I and Figures 1 and 2). After 70 cycles of 1204°C (2200°F) burner rig oxidation, the alloy of this invention lost only about 2% of its weight, as compared to 55% for B1900+HF and 75% for Mar-M-247.
  • a liquid fuel burner is controlled by fuel pressure to maintain the temperature of interest.
  • the specimens are typically cylindrical rods (12mm (0.47") diameter x 82.5mm (3.25") long in this case). Individual specimens can be tested. Multiple specimens are tested in a rotating spindle. Specimen weight and diameter are measured at intervals during the test to monitor the loss of material via oxide spallation. Oxidation rate is proportional to weight loss (greater weight corresponds to greater oxidation rate).
  • a second method of testing oxidation resistance can also be used to characterize the nickel superalloys of the present invention.
  • coupons of a superalloy are suspended from a wire and placed into a furnace maintained at 1149°C +/- 14°C (21000F +/- 250F), while exposed to ambient air.
  • alloy samples are 12.7 x 19mm +/- 3mm (0.50 X 0.75 in. +/-0.12 in.) by 1.02mm +/- 0.25mm (0.040 in. +/- 0.010-in.). Prior to the initial insertion into the furnace, corners and edges on the sample are rounded. Samples are heated in cycles of 24 +/- 4 hours.
  • weight loss from testing at 1149°C (21000F) under cyclic conditions in ambient air for 300 hours does not exceed 10% of the initial sample weight.
  • weight loss from testing at 1149°C (21000F) under cyclic conditions in ambient air for 300 hours does not exceed 5.0% of the initial sample weight.
  • Table III Compositions Evaluated Ni Cr Al Mo W Ta Hf C B Zr Alloy A Bal 9.99 6.50 2.02 3.17 4.07 1.23 0.12 0.004 0.26 Alloy B Bal 10.09 6.53 1.98 3.11 4.10 1.24 0.13 0.004 0.34 Alloy C Bal 10.42 6.66 2.11 2.98 4.19 1.32 0.11 0.010 0.26 Alloy D Bal 9.86 6.66 1.98 3.15 4.32 1.22 0.09 0.004 0.29 * - In weight percent
  • a nickel superalloy component of the present invention is heated to 1079 ⁇ 14°C
  • a nickel superalloy component of the present invention is heated to 1079 ⁇ 14°C (1975 ⁇ 250F) in air for 4 hours and air cooled at a minimum of 22°C/min (400F/min).
  • the component is then heated to 871 ⁇ 14°C (1600 ⁇ 250F) for 16 hours and then air cooled at a minimum of 22°C/min (400F/min). This heat treatment serves to improve the tensile and creep Properties of the superalloy component.
  • the polycrystalline nickel superalloy of the present invention is equiaxed; in another embodiment, the polycrystalline nickel superalloy of the present invention is columnar.
  • the nickel superalloy of the present invention which is shown in Table I has been successfully used as a component of a float wall combustor.

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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)
EP94303644A 1994-05-20 1994-05-20 Superalliage à base de nickel résistant à l'oxydation Expired - Lifetime EP0683239B1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DE1994616110 DE69416110T2 (de) 1994-05-20 1994-05-20 Oxidationsbeständige Superlegierung auf Nickelbasis
EP94303644A EP0683239B1 (fr) 1994-05-20 1994-05-20 Superalliage à base de nickel résistant à l'oxydation
JP12211394A JP3474634B2 (ja) 1994-05-20 1994-06-03 多結晶質ニッケル超合金及びその製造方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP94303644A EP0683239B1 (fr) 1994-05-20 1994-05-20 Superalliage à base de nickel résistant à l'oxydation
JP12211394A JP3474634B2 (ja) 1994-05-20 1994-06-03 多結晶質ニッケル超合金及びその製造方法

Publications (2)

Publication Number Publication Date
EP0683239A1 true EP0683239A1 (fr) 1995-11-22
EP0683239B1 EP0683239B1 (fr) 1999-01-20

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JP (1) JP3474634B2 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2145968A1 (fr) * 2008-07-14 2010-01-20 Siemens Aktiengesellschaft Superalliage renforcé d'amorce de gamme à base de nickel
US20140134353A1 (en) * 2012-11-13 2014-05-15 Honeywell International Inc. Nickel-based superalloys for use on turbine blades
EP2913417B1 (fr) 2014-02-28 2017-01-11 General Electric Company Article et procédé de formation d'un article
US10933469B2 (en) 2018-09-10 2021-03-02 Honeywell International Inc. Method of forming an abrasive nickel-based alloy on a turbine blade tip

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3526499A (en) * 1967-08-22 1970-09-01 Trw Inc Nickel base alloy having improved stress rupture properties
US3776704A (en) * 1968-03-01 1973-12-04 Int Nickel Co Dispersion-strengthened superalloys
US4046560A (en) * 1975-12-30 1977-09-06 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Nickel base alloy
US4126495A (en) * 1973-08-09 1978-11-21 Chrysler Corporation Nickel-base superalloy
US4719080A (en) * 1985-06-10 1988-01-12 United Technologies Corporation Advanced high strength single crystal superalloy compositions
JPH0641664A (ja) * 1992-05-28 1994-02-15 Daido Steel Co Ltd 耐熱弾性機械要素及びその製造方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3526499A (en) * 1967-08-22 1970-09-01 Trw Inc Nickel base alloy having improved stress rupture properties
US3776704A (en) * 1968-03-01 1973-12-04 Int Nickel Co Dispersion-strengthened superalloys
US4126495A (en) * 1973-08-09 1978-11-21 Chrysler Corporation Nickel-base superalloy
US4046560A (en) * 1975-12-30 1977-09-06 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Nickel base alloy
US4719080A (en) * 1985-06-10 1988-01-12 United Technologies Corporation Advanced high strength single crystal superalloy compositions
JPH0641664A (ja) * 1992-05-28 1994-02-15 Daido Steel Co Ltd 耐熱弾性機械要素及びその製造方法

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Week 7327, Derwent World Patents Index; AN 73-38250U *
DATABASE WPI Week 9411, Derwent World Patents Index; AN 94-089607 *
HOLT R.T.; WALLACE W.: "IMPURITIES AND TRACE ELEMENTS IN NICKEL-BASE SUPERALLOYS", INT. METALL. REV., vol. 21, March 1976 (1976-03-01), UK, pages 1 - 24, XP055085369, DOI: doi:10.1179/095066076790136762 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2145968A1 (fr) * 2008-07-14 2010-01-20 Siemens Aktiengesellschaft Superalliage renforcé d'amorce de gamme à base de nickel
WO2010006974A1 (fr) * 2008-07-14 2010-01-21 Siemens Aktiengesellschaft Superalliage à base de nickel renforcé par une phase gamma prime
US8431073B2 (en) 2008-07-14 2013-04-30 Siemens Aktiengesellschaft Nickel base gamma prime strengthened superalloy
US20140134353A1 (en) * 2012-11-13 2014-05-15 Honeywell International Inc. Nickel-based superalloys for use on turbine blades
US8858873B2 (en) * 2012-11-13 2014-10-14 Honeywell International Inc. Nickel-based superalloys for use on turbine blades
EP2913417B1 (fr) 2014-02-28 2017-01-11 General Electric Company Article et procédé de formation d'un article
US10933469B2 (en) 2018-09-10 2021-03-02 Honeywell International Inc. Method of forming an abrasive nickel-based alloy on a turbine blade tip

Also Published As

Publication number Publication date
JP3474634B2 (ja) 2003-12-08
JPH07331365A (ja) 1995-12-19
EP0683239B1 (fr) 1999-01-20

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