US20120282086A1 - Nickel-base alloy - Google Patents
Nickel-base alloy Download PDFInfo
- Publication number
- US20120282086A1 US20120282086A1 US13/100,441 US201113100441A US2012282086A1 US 20120282086 A1 US20120282086 A1 US 20120282086A1 US 201113100441 A US201113100441 A US 201113100441A US 2012282086 A1 US2012282086 A1 US 2012282086A1
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- US
- United States
- Prior art keywords
- percent
- alloy
- article
- titanium
- tantalum
- 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.)
- Abandoned
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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
- C22C19/056—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
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/28—Selecting particular materials; Particular measures relating thereto; Measures against erosion or corrosion
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2300/00—Materials; Properties thereof
- F05D2300/60—Properties or characteristics given to material by treatment or manufacturing
- F05D2300/607—Monocrystallinity
Definitions
- the present invention generally relates to nickel-base alloys for gas turbine applications, which possess a unique combination of mechanical properties, microstructural stability, and resistance to localized pitting and hot corrosion. More specifically, the invention relates to a class of nickel-base alloys having very low fractions of Eta phase and segregated titanium; resulting in improved yield, manufacturability, and repairability of articles formed therefrom.
- the present invention is an improvement to the class of alloys disclosed and claimed in U.S. Pat. No. 6,416,596 B1, issued Jul. 9, 2002 to John H. Wood et al.; which was an improvement to the class of alloys disclosed and claimed in U.S. Pat. No. 3,615,376, issued Oct. 26, 1971 to Earl W. Ross. Both patents are assigned to the assignee hereof.
- the invention retains the advantageous attributes of those alloys; including high strength and ductility, high resistance to creep and fatigue, excellent microstructural stability, and high resistance to localized pitting and hot corrosion in high temperature corrosive environments. This unique combination of properties makes those alloys attractive for use in gas turbines.
- an attribute of the alloys disclosed and claimed in U.S. Pat. No. 6,416,596 is the presence of “Eta” phase, a hexagonal close-packed form of the intermetallic Ni 3 Ti, as well as segregated titanium metal in the solidified alloy.
- Eta phase a hexagonal close-packed form of the intermetallic Ni 3 Ti, as well as segregated titanium metal in the solidified alloy.
- the segregation of titanium also reduces the solidus temperature, increasing the fraction of ⁇ / ⁇ ′ eutectic phases and resulting micro-shrinkages in the solidified alloy.
- the Eta phase in particular, may cause certain articles formed from those alloys to be rejected during the initial forming process, as well as post-forming manufacturing and repair processes.
- the presence of Eta phase may result in degradation of the alloy's mechanical properties during service exposure.
- the alloys exhibit a narrow solidification range (defined as the difference in temperature between the liquidus and solidus of the alloy) and the microstructures of the solidified alloys exhibit a finer ⁇ / ⁇ ′ eutectic and carbide structure than the microstructures of the reference alloys.
- the present invention provides a class of nickel-base alloys for gas turbine applications, and useful articles of manufacture formed therefrom, which possess a unique combination of mechanical properties, microstructural stability, resistance to localized pitting and hot corrosion in high temperature corrosive environments, and high yields during the initial forming process as well as post-forming manufacturing and repair processes.
- the invention is further characterized by having very low fractions of Eta phase and segregated Titanium in the solidified nickel-base alloys.
- the nickel-base alloy comprises, by weight, about 13.7 to about 14.3 percent chromium, about 5.0 to about 10.0 percent cobalt, about 3.5 to about 5.2 percent tungsten, about 2.8 to about 5.2 percent titanium, about 2.8 to about 4.6 percent aluminum, about 0.0 to about 3.5 percent tantalum, about 1.0 to about 1.7 percent molybdenum, about 0.08 to about 0.13 percent carbon, about 0.005 to about 0.02 percent boron, about 0.0 to about 1.5 percent niobium, about 0.0 to about 2.5 percent hafnium, about 0.0 to about 0.04 percent zirconium, and the balance substantially nickel.
- the nickel-base alloy comprises, by weight, about 13.7 to about 14.3 percent chromium, about 5.0 to about 10.0 percent cobalt, about 3.5 to about 5.2 percent tungsten, about 2.8 to about 5.2 percent titanium, about 2.8 to about 4.6 percent aluminum, about 0.0 to about 3.5 percent tantalum, about 1.0 to about 1.7 percent molybdenum, about 0.08 to about 0.13 percent carbon, about 0.005 to about 0.02 percent boron, about 0.0 to about 1.5 percent niobium, about 0.0 to about 2.5 percent hafnium, about 0.0 to about 0.04 percent zirconium, and the balance substantially nickel.
- FIG. 1 is a photomicrograph of Alloy 1, as embodied by the invention.
- FIG. 2 is a photomicrograph of Alloy 2, as embodied by the invention.
- FIG. 3 is a photomicrograph of Alloy 3, as embodied by the invention.
- FIG. 4 is a photomicrograph of Alloy 4, as embodied by the invention.
- FIG. 5 is a photomicrograph of Alloy 5, as embodied by the invention.
- FIG. 6 is a photomicrograph of Alloy 6, as embodied by the invention.
- FIG. 7 is a photomicrograph of Alloy 7, as embodied by the invention.
- FIG. 8 is a plot showing normalized tensile strength of Alloys 1 to 4, measured at 20° C. (68° F.) and 760° C. (1400° F.), shown as the fraction of the average tensile strength of the reference alloys at those temperatures.
- FIG. 9 is a plot showing normalized creep life of Alloys 1 to 4, in terms of the times to 1.0% strain at 732° C. (1350° F.), shown as the fraction of the average creep life of the reference alloys at the same strain and temperature.
- FIG. 10 is a plot showing the machining energy (in Joules) required for Alloys 1 and 2 during a milling operation.
- the present invention was the result of an investigation to develop a class of nickel-base alloys for gas turbine applications, and useful articles of manufacture formed therefrom, which possess a unique combination of mechanical properties, microstructural stability, resistance to localized pitting and hot corrosion in high temperature corrosive environments, and high yields during the initial forming process as well as post-forming manufacturing and repair processes.
- the invention is further characterized by having very low fractions of Eta phase and segregated Titanium in the solidified nickel-base alloys.
- the nickel-base alloy comprises, by weight, about 13.7 to about 14.3 percent chromium, about 5.0 to about 10.0 percent cobalt, about 3.5 to about 5.2 percent tungsten, about 2.8 to about 5.2 percent titanium, about 2.8 to about 4.6 percent aluminum, about 0.0 to about 3.5 percent tantalum, about 1.0 to about 1.7 percent molybdenum, about 0.08 to about 0.13 percent carbon, about 0.005 to about 0.02 percent boron, about 0.0 to about 1.5 percent niobium, about 0.0 to about 2.5 percent hafnium, about 0.0 to about 0.04 percent zirconium, and the balance substantially nickel.
- the nickel-base alloy is characterized by having very low fractions of Eta phase and segregated Titanium; and comprises, by weight, about 13.7 to about 14.3 percent chromium, about 5.0 to about 10.0 percent cobalt, about 3.5 to about 5.2 percent tungsten, about 2.8 to about 5.2 percent titanium, about 2.8 to about 4.6 percent aluminum, about 0.0 to about 3.5 percent tantalum, about 1.0 to about 1.7 percent molybdenum, about 0.08 to about 0.13 percent carbon, about 0.005 to about 0.02 percent boron, about 0.0 to about 1.5 percent niobium, about 0.0 to about 2.5 percent hafnium, about 0.0 to about 0.04 percent zirconium, and the balance substantially nickel.
- the nickel-base alloy comprises, by weight, about 13.9 percent chromium, about 9.5 percent cobalt, about 4.5 percent tungsten, about 4.2 percent titanium, about 3.7 percent aluminum, about 3.4 percent tantalum, about 1.6 percent molybdenum, about 0.1 percent carbon, about 0.01 percent boron, less than 0.01 percent zirconium, and the balance substantially nickel.
- the nickel-base alloy comprises, by weight, about 13.9 percent chromium, about 9.5 percent cobalt, about 4.2 percent tungsten, about 3.7 percent titanium, about 3.7 percent aluminum, about 3.2 percent tantalum, about 1.5 percent molybdenum, about 0.1 percent carbon, about 0.01 percent boron, about 0.002 percent zirconium, and the balance substantially nickel.
- the article may be formed by a casting method comprising the following steps: (1) preparing an ingot of the composition in the amounts stated above, (2) remelting the ingot and casting it to a form of the size and shape of the desired article, (3) heat treating the article in a suitable atmosphere and in accordance with a suitable time and temperature schedule, and (4) coating the article, if desired, with a suitable material for thermal or environmental protection.
- the grain structure of the cast articles may be either equiaxed (having no preferred orientation), directionally solidified (having a preferred orientation), or single crystal (having no grain boundaries).
- the article may be a gas turbine bucket or other form of rotating airfoil, or a gas turbine nozzle or other form of stationary airfoil, or another gas turbine component, that is located in the gas turbine hot section and designed in such a manner as to take advantage of the beneficial properties of the alloy.
- the nickel-base alloy comprises, by weight, about 13.7 to about 14.3 percent chromium, about 5.0 to about 10.0 percent cobalt, about 3.5 to about 5.2 percent tungsten, about 2.8 to about 5.2 percent titanium, about 2.8 to about 4.6 percent aluminum, about 0.0 to about 3.5 percent tantalum, about 1.0 to about 1.7 percent molybdenum, about 0.08 to about 0.13 percent carbon, about 0.005 to about 0.02 percent boron, about 0.0 to about 1.5 percent niobium, about 0.0 to about 2.5 percent hafnium, about 0.0 to about 0.04 percent zirconium, and the balance substantially nickel; and the article may be formed by a casting method that produces gas turbine airfoils or other components having either an equiaxed, directionally solidified, or single crystal grain structure.
- the nickel-base alloy comprises, by weight, about 13.9 percent chromium, about 9.5 percent cobalt, about 4.5 percent tungsten, about 4.2 percent titanium, about 3.7 percent aluminum, about 3.4 percent tantalum, about 1.6 percent molybdenum, about 0.1 percent carbon, about 0.01 percent boron, less than 0.01 percent zirconium, and the balance substantially nickel; and the article may be formed by a casting method that produces gas turbine airfoils or other components having an equiaxed grain structure.
- the nickel-base alloy comprises, by weight, about 13.9 percent chromium, about 9.5 percent cobalt, about 4.2 percent tungsten, about 3.7 percent titanium, about 3.7 percent aluminum, about 3.2 percent tantalum, about 1.5 percent molybdenum, about 0.1 percent carbon, about 0.01 percent boron, about 0.002 percent zirconium, and the balance substantially nickel; and the article may be formed by a casting method that produces gas turbine airfoils or other components having a directionally solidified grain structure.
- a feature of embodiments of the present invention is that the contents of aluminum and titanium and their relative ratios may be adjusted in such a manner that reduces the fractions of the ⁇ / ⁇ ′ eutectic phase, Eta phase, and segregated titanium that form during alloy solidification.
- the solidified alloys are substantially free of Eta phase when the ratio of aluminum to titanium is between about 0.8 and about 1.0, by weight.
- a further benefit is a strengthening effect that may be due to an increase in ⁇ ′ phase in the ⁇ matrix.
- the contents of aluminum and tantalum and their relative ratios may be adjusted in such a manner that further reduces the formation of Eta phase, while maintaining the fraction of ⁇ ′ phase, in the solidified alloy.
- the solidified alloys are substantially free of Eta phase when the ratio of aluminum to tantalum is between about 0.9 and about 1.3, by weight.
- Another feature of embodiments of the present invention is that the content of tantalum may be reduced and the content of niobium may be increased, such that niobium may be entirely substituted for tantalum if desired.
- Another feature of embodiments of the present invention is that the contents of tantalum and tungsten may be adjusted in such a manner that results in a combination of precipitation and solid solution strengthening.
- Alloys 2 and 3 are variations of the reference alloys, having ratios of aluminum to titanium near the upper limit (Alloy 2) and lower limit (Alloy 3) of the ranges specified for the reference alloys.
- Alloys 1 and 4 are derivations of the reference alloys, having higher ratios of aluminum to titanium, as well as higher contents of tantalum and tungsten, than the ranges specified for the reference alloys.
- the microstructures of the four experimental alloys from Table 1 are shown in FIGS. 1 to 4 , respectively.
- the microstructural evaluations showed that Alloy 1 had no visible Eta phase, a low fraction of eutectic phase, and a low fraction of carbides ( FIG. 1 ); Alloy 2 had no visible Eta phase, an expected fraction of eutectic phase, and an expected fraction of carbides ( FIG. 2 ); Alloy 3 had visible Eta phase, an expected fraction of eutectic phase, and an expected fraction of carbides ( FIG. 3 ); and Alloy 4 had no visible Eta phase, a low fraction of eutectic phase, and a low fraction of carbides ( FIG. 4 ).
- Alloy 5 is a derivation of the reference alloys, having a higher ratio of aluminum to titanium, as well as higher contents of tantalum and tungsten, than the ranges specified for the reference alloys; while Alloys 6 and 7 are variations of the reference alloys.
- FIGS. 5 to 7 The microstructures of the three experimental alloys from Table 2 are shown in FIGS. 5 to 7 , respectively.
- the microstructural evaluations showed that Alloy 5 had no visible Eta phase and a low fraction of eutectic phase ( FIG. 5 ); Alloy 6 had no visible Eta phase and an expected fraction of eutectic phase ( FIG. 6 ); and Alloy 7 had visible Eta phase and an expected fraction of eutectic phase ( FIG. 7 ).
- FIGS. 8 to 10 The results of representative mechanical and manufacturing evaluations performed on the test articles prepared from the four experimental alloys from Table 1 are shown in FIGS. 8 to 10 , respectively. These results show that all four experimental alloys have tensile strength that is above 90% of the tensile strength of the reference alloys at both 20° C. and 760° C. ( FIG. 8 ). The results also showed that the creep life of Alloy 1 at 732° C. is generally equal to or greater than the creep life of the reference alloys at 1.0% strain ( FIG. 9 ), and that Alloy 1 required less machining energy than Alloy 2 (a variation of the reference alloys) during milling ( FIG. 12 ).
- the present invention contemplates the use in a class of nickel-base alloys of the elements aluminum, titanium, tantalum, and tungsten in a novel manner that advantageously improves both manufacturing yield and mechanical properties of alloys having superior microstructural stability and resistance to localized pitting and hot corrosion in high temperature corrosive environments.
- the broad, preferred, and nominal compositions (by weight) of this class of nickel-base alloys are summarized in Table 3.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
- Coating By Spraying Or Casting (AREA)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/100,441 US20120282086A1 (en) | 2011-05-04 | 2011-05-04 | Nickel-base alloy |
EP12166469.2A EP2520678B1 (fr) | 2011-05-04 | 2012-05-02 | Alliages à base de nickel |
CN201210205495.2A CN102766787B (zh) | 2011-05-04 | 2012-05-04 | 镍基合金 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/100,441 US20120282086A1 (en) | 2011-05-04 | 2011-05-04 | Nickel-base alloy |
Publications (1)
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US20120282086A1 true US20120282086A1 (en) | 2012-11-08 |
Family
ID=46084846
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US13/100,441 Abandoned US20120282086A1 (en) | 2011-05-04 | 2011-05-04 | Nickel-base alloy |
Country Status (3)
Country | Link |
---|---|
US (1) | US20120282086A1 (fr) |
EP (1) | EP2520678B1 (fr) |
CN (1) | CN102766787B (fr) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2567492A (en) * | 2017-10-16 | 2019-04-17 | Oxmet Tech Limited | A nickel-based alloy |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB201309404D0 (en) * | 2013-05-24 | 2013-07-10 | Rolls Royce Plc | A nickel alloy |
US9404388B2 (en) * | 2014-02-28 | 2016-08-02 | General Electric Company | Article and method for forming an article |
CN104894434B (zh) * | 2014-03-04 | 2018-04-27 | 中国科学院金属研究所 | 一种组织稳定的抗热腐蚀镍基高温合金 |
CN113481413A (zh) * | 2021-05-24 | 2021-10-08 | 深圳市万泽中南研究院有限公司 | 一种定向凝固镍基高温合金、透平叶片和燃气轮机 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3650635A (en) * | 1970-03-09 | 1972-03-21 | Chromalloy American Corp | Turbine vanes |
US6231692B1 (en) * | 1999-01-28 | 2001-05-15 | Howmet Research Corporation | Nickel base superalloy with improved machinability and method of making thereof |
US6818077B2 (en) * | 2002-12-17 | 2004-11-16 | Hitachi, Ltd. | High-strength Ni-base superalloy and gas turbine blades |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3615376A (en) | 1968-11-01 | 1971-10-26 | Gen Electric | Cast nickel base alloy |
US6416596B1 (en) | 1974-07-17 | 2002-07-09 | The General Electric Company | Cast nickel-base alloy |
US20030111138A1 (en) * | 2001-12-18 | 2003-06-19 | Cetel Alan D. | High strength hot corrosion and oxidation resistant, directionally solidified nickel base superalloy and articles |
US20040200549A1 (en) * | 2002-12-10 | 2004-10-14 | Cetel Alan D. | High strength, hot corrosion and oxidation resistant, equiaxed nickel base superalloy and articles and method of making |
US6902633B2 (en) | 2003-05-09 | 2005-06-07 | General Electric Company | Nickel-base-alloy |
US20070095441A1 (en) * | 2005-11-01 | 2007-05-03 | General Electric Company | Nickel-base alloy, articles formed therefrom, and process therefor |
CN101525706B (zh) * | 2009-04-17 | 2011-01-12 | 东华大学 | 一种镍基单晶高温合金中提高高温抗蠕变性能的改性方法 |
US8226886B2 (en) * | 2009-08-31 | 2012-07-24 | General Electric Company | Nickel-based superalloys and articles |
-
2011
- 2011-05-04 US US13/100,441 patent/US20120282086A1/en not_active Abandoned
-
2012
- 2012-05-02 EP EP12166469.2A patent/EP2520678B1/fr active Active
- 2012-05-04 CN CN201210205495.2A patent/CN102766787B/zh active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3650635A (en) * | 1970-03-09 | 1972-03-21 | Chromalloy American Corp | Turbine vanes |
US6231692B1 (en) * | 1999-01-28 | 2001-05-15 | Howmet Research Corporation | Nickel base superalloy with improved machinability and method of making thereof |
US6818077B2 (en) * | 2002-12-17 | 2004-11-16 | Hitachi, Ltd. | High-strength Ni-base superalloy and gas turbine blades |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2567492A (en) * | 2017-10-16 | 2019-04-17 | Oxmet Tech Limited | A nickel-based alloy |
GB2567492B (en) * | 2017-10-16 | 2020-09-23 | Oxmet Tech Limited | A nickel-based alloy |
Also Published As
Publication number | Publication date |
---|---|
EP2520678B1 (fr) | 2019-03-20 |
CN102766787A (zh) | 2012-11-07 |
CN102766787B (zh) | 2016-09-28 |
EP2520678A2 (fr) | 2012-11-07 |
EP2520678A3 (fr) | 2016-12-14 |
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Owner name: GENERAL ELECTRIC COMPANY, NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FENG, GANJIANG;SCHAEFFER, JON CONRAD;BALSONE, STEPHEN JOSEPH;AND OTHERS;SIGNING DATES FROM 20110329 TO 20110415;REEL/FRAME:026222/0278 |
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