EP1038982A1 - Einkristalline Superlegierungskörpern mit verminderter Rekristallisierung der Körnern - Google Patents

Einkristalline Superlegierungskörpern mit verminderter Rekristallisierung der Körnern Download PDF

Info

Publication number
EP1038982A1
EP1038982A1 EP00105884A EP00105884A EP1038982A1 EP 1038982 A1 EP1038982 A1 EP 1038982A1 EP 00105884 A EP00105884 A EP 00105884A EP 00105884 A EP00105884 A EP 00105884A EP 1038982 A1 EP1038982 A1 EP 1038982A1
Authority
EP
European Patent Office
Prior art keywords
casting
single crystal
carbon
weight
heat treating
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.)
Withdrawn
Application number
EP00105884A
Other languages
English (en)
French (fr)
Inventor
John Corrigan
Russell G. Vogt
John R. Mihalisin
Dean L. Schmiedeknecht
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.)
Howmet Corp
Original Assignee
Howmet Research Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Howmet Research Corp filed Critical Howmet Research Corp
Publication of EP1038982A1 publication Critical patent/EP1038982A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • 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%
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/20—Carburising

Definitions

  • the present invention relates to nickel base superalloy castings and, more particularly, to a method of heat treating single crystal superalloy castings in a manner to reduce or localize deleterious extraneous grain recrystallization during heat treatment.
  • U.S. Patent 4 643 782 describes single crystal castings made from a nickel base superalloy having a composition consisting essentially of, in weight %, of 6.4% to 6.8% Cr, 9.3% to 10.0% Co, 0.5% to 0.7% Mo, 6.2% to 6.6% W, 6.3% to 6.7% Ta, 5.45% to 5.75% Al, 0.8% to 1.2% Ti, 2.8% to 3.2% Re, 0.07 to 0.12% Hf and balance essentially nickel. Carbon is held to incidental impurity levels of for example 60 ppm maximum C in the alloy.
  • the present invention provides a method of making of superalloy single crystal castings, such as gas turbine engine single crystal blades and vanes (airfoils), in a manner to address the problem of grain recrystallization during heat treatment of the single crystal castings.
  • the invention involves the discovery that grain recrystallization can be reduced by solution heat treating the single crystal castings in the presence of gaseous species carburizing relative to the superalloy castings so as to introduce carbon into the castings in an effective amount to reduce recrystallized grains during heat treatment.
  • a carburizing atmosphere can be provided by introducing a mixture of carbon monoxide and an inert gas, such as argon, into the heat treatment furnace or by heat treating in a furnace having a component, such as heating elements, that inherently provides a carburizing atmosphere during heat treatment.
  • a furnace to this end typically comprises heating elements, heat shields and/or other furnace components or inserts comprising graphite or other carbon-bearing material as a source of carbon for reaction with oxygen to form a carbon-bearing gas, such as carbon monoxide, in-situ in the furnace that is carburizing relative to the castings.
  • the carbon concentration of at least the outer surface region of the superalloy single crystal castings is locally increased during heat treatment as compared to the nominal carbon concentration of the bulk superalloy casting as evidenced, for example, by the presence of blocky carbides of one or more alloying elements, which carbides are not present when the superalloy casting is heat treated under vacuum or inert gas atmosphere only in the absence of a carburizing gas species in the furnace.
  • the carbides form in the microstructure in a manner to pin any recrystallized grain boundaries during solution heat treatment and retard, limit and localize their growth in a manner to improve the yield of acceptable heat treated single crystal castings.
  • the present invention involves heat treating nickel base superalloys formulated for single crystal casting in a manner to unexpectedly and surprisingly substantially reduce or localize grain recrystallization after heat treatment of the casting at elevated temperature, such as a high temperature solution heat treatment to dissolve or solution most of the eutectic and coarse gamma prime phases present in the as-cast microstructure. Improved yields of acceptable heat treated single crystal castings are thereby achieved.
  • the present invention can be practiced on a variety of low carbon nickel base superalloys that are formulated for single crystal casting and include W, Ta, Mo, Co, Al and Cr as important alloying elements as well as optionally Ti, Re, Y, Hf, one or more rare earth elements such as La, B, and Mg as intentional alloying elements and that suffer undesirable grain recrystallization upon heat treatment.
  • Such grain recrystallization prone nickel base superalloys typically have carbon concentration less than about 200 ppm by weight (about 0.02 weight % C) with some less than about 100 ppm C (about 0.01 weight % C), although the invention may be practiced with superalloys having other carbon concentrations to reduce grain recrystallization in a particular nickel base superalloy.
  • Nickel base superalloys formulated for casting single crystal castings such as single crystal airfoils (blades and vanes), and heat treatable pursuant to the invention include, but are not limited to, those described in U.S. Patents 4 643 782 and 5 366 695 the teachings of which are incorporated herein by reference with respect to particular alloy compositions.
  • An illustrative nickel base superalloy casting composition heat treatable pursuant to the present invention consists essentially of, in weight % or parts per million (ppm) by weight, of about 6% to 6.8% Cr, about 8% to 10% Co, about 0.5% to 0.7% Mo, about 6.2% to 6.6% W, about 6.3% to 7% Ta, about 5.4% to 5.8% Al, about 0.6% to 1.2% Ti, about 0.10% to 0.3% Hf, up to about 200 ppm by weight B, up to about 50 ppm by weight Mg, up to about 200 ppm by weight carbon, and balance essentially Ni and castable to provide a single crystal microstructure, especially for gas turbine engine blades and vanes (i.e. airfoils).
  • ppm parts per million
  • An illustrative low carbon, high Re nickel base superalloy casting composition heat treatable pursuant to the present invention consists essentially of, in weight %, of about 1.5% to 5% Cr, about 1.5% to 10% Co, about 0.25% to 2% Mo, about 3.5% to 7.5% W, about 7% to 10% Ta, about 5% to 7% Al, up to about 1.2% Ti, about 5% to 7% Re, up to about 0.15% Hf, up to about 0.5% Nb, C less than about 0.02% or at incidental impurity level, and balance essentially Ni and castable to provide a single crystal microstructure, especially for gas turbine engine blades and vanes (i.e. airfoils).
  • An illustrative low carbon, high Cr nickel base superalloy casting composition heat treatable pursuant to the present invention consists essentially of, in weight %, of about 11% to 16% Cr, about 2% to 8% Co, about 0.2% to 2% Mo, about 3.5% to 7.5% W, about 4% to 6% Ta, about 3% to 6% Al, about 2% to about 5% Ti, up to about 0.2% Nb, C less than about 0.02% or at incidental impurity level, and balance essentially Ni and castable to provide a single crystal microstructure, especially for gas turbine engine blades and vanes (i.e. airfoils).
  • Single crystal gas turbine engine blades were conventionally cast using the Bridgeman withdrawal technique from commercially available CMSX-4 nickel base superalloy, described in US Patent 4 643 782, and were subjected in the as-cast condition after removal of a ceramic shell mold and a ceramic core to solution heat treatments in various atmospheres.
  • the nominal composition, in weight %, of the single crystal blades was 6.4% Cr, 9.7% Co, 0.6% Mo, 6.4% W, 6.5% Ta, 5.6% Al, 1.0% Ti, 2.9% Re, 0.10% Hf, 30 ppm by weight C and balance essentially Ni and impurities.
  • the ceramic shell mold and core were removed completely from the castings in conventional manner using a mechanical knock-out procedure and chemical leaching.
  • the single crystal blade castings then were solution heat treated in various furnaces using various atmospheres. After heat treatment, the castings were examined for the presence of recrystallized grains on the casting surfaces.
  • the cast single crystal blades were solution heat treated in various heat treatment furnaces.
  • One type of furnace included graphite electrical resistance heating element and graphite sides or heat shield liners.
  • Another type of furnace included molybdenum electrical resistance heating elements and graphite sides or heat shield liners.
  • Different heat treatment atmospheres were provided for different heat treatment runs in the different types of furnaces.
  • one heat treatment run involved providing a vacuum of less than 5 microns in a furnace having molybdenum heating elements and graphite heat shields or liners and then introducing a mixture of argon and 10% by volume CO at a flow rate during continued vacuum pump evacuation of the furnace to maintain 400 microns partial pressure of argon plus CO in the furnace as the atmosphere during heat treatment.
  • the argon/10% by volume CO gas mixture was introduced from a conventional gas cylinder having a mixture of argon and 10% by volume CO therein. The mixture was introduced after the furnace temperature reached 1900 degrees F so as to reduce chromium vaporization from the castings.
  • a total of 10 cast single crystal blades were solution heat treated in this furnace by slowly heating the castings to a solutioning temperature of 2400 degrees F plus or minus 15 degrees F over 11 hours. The solutioning temperature was held for 6 hours, and the castings were cooled to room temperature over a time of 1 hour.
  • the solution heat treatment dissolved most of the eutectic and coarse gamma prime phases in the as-cast microstructure.
  • the only recrystallized grains observed were initiated proximate a core print (at a blade tip) with the recrystallized grains localized to an extent that they existed outside the finished casting dimensions for the particular blade involved; i.e. such that the localized amount of recrystallized grains on the heat treated blade would be removed by subsequent finish machining of the blade.
  • blocky carbides rich in Ta and Ti having a lateral dimension (e.g. diameter) of less than 0.5 mil (0.0005 inch) were observed to exist throughout the airfoil and pinning the recrystallized grain boundaries as illustrated in Figure 1 by the arrow.
  • the carbides were determined to include Ta in the approximate range of 71-77 weight % Ta, Ti in approximate range of 9-10 weight % Ti, Hf in approximate range of 2-7 weight % Hf, Ni in approximate range of 3-4 weight % Ni with other elements such as Co, W, Cr, Fe, also present in lesser amounts.
  • the carbides were formed predominantly along cast surfaces, providing a high population of carbides in thin sections of the castings where grain growth is more likely to be a problematic.
  • the carbides were attributed to the carburization of the castings, resulting in introduction of carbon into the castings during heat treatment. For example, typical carbon concentration at the airfoil surface and of the bulk airfoil was twice as high (at least 100% higher) as the as-cast carbon content at the airfoil surface.
  • the as-cast carbon concentration of the bulk airfoil and bulk root were increased from about 38 ppm by weight C to 113 ppm and 89 ppm by weight carbon for the airfoil and root, respectively.
  • the carbon content at the airfoil surface was even higher, being about 171 ppm by weight C after the above heat treatment.
  • the present invention provides single crystal castings having carbon concentrations increased by the heat treatment in an amount discovered to form carbides in-situ in the heat treated microstructure that pin recrystallized grain boundaries and retard, limit and localize their growth to reduce recrystallized grains that are cause for rejection of the single crystal castings and increase yield of acceptable heat treated castings.
  • Practice of the invention as described above produced a six times increase in yield of acceptable heat treated single crystal turbine blade castings.
  • the present invention envisions use of carburizing atmospheres or gaseous carburizing species other than carbon monoxide that are effective to introduce carbon to single crystal nickel base superalloy castings during their heat treatment in amounts effective to reduce or localize recrystallized grains.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Furnace Details (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
EP00105884A 1999-03-26 2000-03-20 Einkristalline Superlegierungskörpern mit verminderter Rekristallisierung der Körnern Withdrawn EP1038982A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US276859 1988-11-25
US27685999A 1999-03-26 1999-03-26

Publications (1)

Publication Number Publication Date
EP1038982A1 true EP1038982A1 (de) 2000-09-27

Family

ID=23058370

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00105884A Withdrawn EP1038982A1 (de) 1999-03-26 2000-03-20 Einkristalline Superlegierungskörpern mit verminderter Rekristallisierung der Körnern

Country Status (2)

Country Link
EP (1) EP1038982A1 (de)
JP (1) JP2000319769A (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1211336A1 (de) * 2000-11-30 2002-06-05 ONERA (Office National d'Etudes et de Recherches Aérospatiales) Superlegierung auf Nickelbasis für Einkristallturbinenschaufeln von industriellen Turbinen mit hoher Beständigkeit gegen Heisskorrosion
EP1211335A1 (de) * 2000-11-30 2002-06-05 ONERA (Office National d'Etudes et de Recherches Aérospatiales) Superlegierung auf Nickelbasis mit sehr hoher Beständigkeit gegen Heisskorrosion für Einkristallturbinenschaufeln von industriellen Turbinen
US6675586B2 (en) 2001-06-27 2004-01-13 Siemens Aktiengesellschaft Heat shield arrangement for a component carrying hot gas, in particular for structural parts of gas turbines
US6719853B2 (en) 2001-04-27 2004-04-13 Siemens Aktiengesellschaft Method for restoring the microstructure of a textured article and for refurbishing a gas turbine blade or vane
GB2404924A (en) * 2003-08-11 2005-02-16 Hitachi Ltd Nickel-based single crystal superalloy
CN107119325A (zh) * 2017-06-26 2017-09-01 中国科学院金属研究所 一种消除激光3d打印单晶高温合金再结晶倾向的方法
CN112160031A (zh) * 2020-09-10 2021-01-01 中国科学院金属研究所 一种提高定向凝固柱晶或单晶高温合金铸件高温持久寿命的方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014150342A1 (en) * 2013-03-15 2014-09-25 United Technologies Corporation Cast component having corner radius to reduce recrystallization

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2075548A (en) * 1980-05-09 1981-11-18 United Technologies Corp Corrosion Resistant Nickel Base Superalloys Containing Manganese
US4849030A (en) * 1986-06-09 1989-07-18 General Electric Company Dispersion strengthened single crystal alloys and method
US5366695A (en) * 1992-06-29 1994-11-22 Cannon-Muskegon Corporation Single crystal nickel-based superalloy
US5556484A (en) * 1995-04-26 1996-09-17 General Electric Company Method for reducing abnormal grain growth in Ni-base superalloys
US5759303A (en) * 1993-03-18 1998-06-02 Howmet Research Corporation Clean single crystal nickel base superalloy
JPH11310839A (ja) * 1998-04-28 1999-11-09 Hitachi Ltd 高強度Ｎｉ基超合金方向性凝固鋳物

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2075548A (en) * 1980-05-09 1981-11-18 United Technologies Corp Corrosion Resistant Nickel Base Superalloys Containing Manganese
US4849030A (en) * 1986-06-09 1989-07-18 General Electric Company Dispersion strengthened single crystal alloys and method
US5366695A (en) * 1992-06-29 1994-11-22 Cannon-Muskegon Corporation Single crystal nickel-based superalloy
US5759303A (en) * 1993-03-18 1998-06-02 Howmet Research Corporation Clean single crystal nickel base superalloy
US5556484A (en) * 1995-04-26 1996-09-17 General Electric Company Method for reducing abnormal grain growth in Ni-base superalloys
JPH11310839A (ja) * 1998-04-28 1999-11-09 Hitachi Ltd 高強度Ｎｉ基超合金方向性凝固鋳物

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Section Ch Week 200011, Derwent World Patents Index; Class M, Page 22, AN 2000-119276 *
PATENT ABSTRACTS OF JAPAN vol. 2000, no. 02 29 February 2000 (2000-02-29) *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1211336A1 (de) * 2000-11-30 2002-06-05 ONERA (Office National d'Etudes et de Recherches Aérospatiales) Superlegierung auf Nickelbasis für Einkristallturbinenschaufeln von industriellen Turbinen mit hoher Beständigkeit gegen Heisskorrosion
EP1211335A1 (de) * 2000-11-30 2002-06-05 ONERA (Office National d'Etudes et de Recherches Aérospatiales) Superlegierung auf Nickelbasis mit sehr hoher Beständigkeit gegen Heisskorrosion für Einkristallturbinenschaufeln von industriellen Turbinen
US6719853B2 (en) 2001-04-27 2004-04-13 Siemens Aktiengesellschaft Method for restoring the microstructure of a textured article and for refurbishing a gas turbine blade or vane
US6675586B2 (en) 2001-06-27 2004-01-13 Siemens Aktiengesellschaft Heat shield arrangement for a component carrying hot gas, in particular for structural parts of gas turbines
GB2404924A (en) * 2003-08-11 2005-02-16 Hitachi Ltd Nickel-based single crystal superalloy
GB2404924B (en) * 2003-08-11 2005-07-27 Hitachi Ltd Single-crystal Ni-based superalloy with high temperature strength, oxidation resistance and hot corrosion resistance
US7306682B2 (en) 2003-08-11 2007-12-11 Hitachi, Ltd. Single-crystal Ni-based superalloy with high temperature strength, oxidation resistance and hot corrosion resistance
CN107119325A (zh) * 2017-06-26 2017-09-01 中国科学院金属研究所 一种消除激光3d打印单晶高温合金再结晶倾向的方法
CN107119325B (zh) * 2017-06-26 2019-03-12 中国科学院金属研究所 一种消除激光3d打印单晶高温合金再结晶倾向的方法
CN112160031A (zh) * 2020-09-10 2021-01-01 中国科学院金属研究所 一种提高定向凝固柱晶或单晶高温合金铸件高温持久寿命的方法
CN112160031B (zh) * 2020-09-10 2022-03-22 中国科学院金属研究所 一种提高定向凝固柱晶或单晶高温合金铸件高温持久寿命的方法

Also Published As

Publication number Publication date
JP2000319769A (ja) 2000-11-21

Similar Documents

Publication Publication Date Title
US6231692B1 (en) Nickel base superalloy with improved machinability and method of making thereof
US6908518B2 (en) Nickel base superalloys and turbine components fabricated therefrom
EP2770081B1 (de) Nickelbasislegierungen und Verfahren zur Wärmebehandlung von Nickelbasislegierungen
EP3441489A1 (de) Verfahren zur herstellung eines legierungselements auf ni-basis
EP3183372B1 (de) Verbesserte superlegierungen durch zirkoniumzugabe
EP2778241B1 (de) Hitzebeständige superlegierung auf nickelbasis
JP5398123B2 (ja) ニッケル系合金
EP1431405B1 (de) Beschichtete Artikel aus Superlegierung auf Nickel Basis
US20220380867A1 (en) Precipitation Hardenable Cobalt-Nickel Base Superalloy And Article Made Therefrom
EP0150917B1 (de) Monokristalline Legierung auf Nickelbasis
EP1433865A1 (de) Hochfeste Superlegierung auf Nickelbasis und Gasturbinenschaufeln
JP3915324B2 (ja) チタンアルミナイド合金材料及びその鋳造品
EP1038982A1 (de) Einkristalline Superlegierungskörpern mit verminderter Rekristallisierung der Körnern
Mišković et al. Microstructural investigation of IN 939 superalloy
US6159314A (en) Nickel-base single-crystal superalloys, method for manufacturing the same, and gas turbine parts prepared therefrom
JP4222540B2 (ja) ニッケル基単結晶超合金、その製造方法およびガスタービン高温部品
US20020007877A1 (en) Casting of single crystal superalloy articles with reduced eutectic scale and grain recrystallization
US5882446A (en) Heat treatment process for material bodies made of nickel base superalloys
RU2274671C1 (ru) Способ производства безуглеродистых литейных жаропрочных сплавов на основе никеля
US20050000603A1 (en) Nickel base superalloy and single crystal castings
Agh et al. Investigation of the stress rupture behavior of GTD-111 superalloy melted by VIM/VAR
EP1889939B1 (de) Legierung und Verfahren zur Behandlung von Titanaluminid
EP1438441B1 (de) Verfahren zur wärmebehandlung von legierungen mit elementen zur erhöhung der korngrenzfestigkeit
JPH06240428A (ja) Ｔｉ−Ａｌ系金属間化合物基合金の製造方法
JP2004332114A (ja) ニッケル基超合金及び単結晶鋳造品

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 20010313

AKX Designation fees paid

Free format text: DE FR GB

17Q First examination report despatched

Effective date: 20010706

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Withdrawal date: 20011030