Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3542530 A
Publication typeGrant
Publication dateNov 24, 1970
Filing dateMay 23, 1968
Priority dateMay 23, 1968
Also published asDE1924071B1
Publication numberUS 3542530 A, US 3542530A, US-A-3542530, US3542530 A, US3542530A
InventorsFrank P Talboom Jr, Johannes Grafwallner
Original AssigneeUnited Aircraft Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Nickel or cobalt base with a coating containing iron chromium and aluminum
US 3542530 A
Abstract  available in
Images(3)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

3,542,530 NICKEL R COBALT BASE WITH A COAT- IN G CONTAINING IRON CHROMIUM AND ALUMINUM Frank P. Talboom, Jr., Glastonbury, and Johannes Grafwallner, South Glastonbury, Conn, assignors to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware No Drawing. Filed May 23, 1968, Ser. No. 731,650 Int. Cl. B32b 15/00 US. Cl. 29183.5 4 Claims ABSTRACT OF THE DISCLOSURE A coating composition consisting of iron, chromium, aluminum and yttrium is provided to impart superior hightemperature oxidation, sulfidation, erosion and thermal Sl'l10Ck resistance to the nickel-base and cobalt-base supera loys.

CROSS-REFERENCE TO RELATED APPLICATION This application is related to the copending application entitled Method for Coating the Superalloys, Ser. No. 731,649, by R. C. Elam, J. O. Petrusha and F. P. Talboom, Jr.

BACKGROUND OF THE INVENTION The present invention relates to coated articles and coating compositions therefor and, more particularly, to a coating composition of iron, chromium, aluminum and yttrium having particular utility in imparting high temperature oxidation resistance to the nickel-base and cobalt-base superalloys.

As described in the patent to Hoyt et al. 1,995,923, alloys in the iron-chromium-aluminum system have been available for a number of years, particularly for use in high-temperature heating elements. More recently, it has been found that addition of small amounts of yttrium, together with the aluminum, will provide superior oxidation resistance, improved workability and better oxide films to the iron-chromium alloys. In the patent to McGurty et al. 3,027,252, for example, there is described an alloy consisting of, by weight, 20-95 percent chromium, 0.5-4 percent aluminum, 0.53 percent yttrium, balance iron. The patent to Wukusick, 3,298,826, discloses a somewhat similar alloy consisting of, by weight, Ol5 percent chromium, 05-12 percent aluminum, 0.1-3 percent yttrium, balance iron.

Basically, the prior art has been concerned with providing a good high temperature alloy with not only good oxidation resistance but also good structural strength and workability, and the chemistry of the various related alloys was formulated on this basis. The criteria for a coating composition, however, are apt to be different from those applicable to structural alloys. This has been borne out by tests establishing that the prior art formulations are unsatisfactory in providing long term surface protection to the nickel-base and cobalt-base superalloys when used as coatings therefor at the temperatures of interest in the current gas turbine engines.

SUMMARY OF THE INVENTION Briefly stated, the present invention contemplates a coating composition comprising, by weight, about 20-50 percent chromium, -20 percent aluminum, 0.03-2 percent selected from the group consisting of yttrium and the rare earth elements, balance iron, and articles coated with this composition.

In its most preferred embodiment, the coating of this invention is formulated to a composition comprising, by

rates- Patent Oice Patented Nov. 24, 1970 weight, 2529 percent chromium, 12-14 percent aluminum, 0.60.9 percent yttrium, balance iron, as applied to the nickel-base and cobalt-base superalloys.

DESCRIPTION OF THE PREFERRED EMBODIMENTS While the preferred coating is applicable to the nickelbase and cobalt-base alloys generally, it was formulated to the composition having particularly efficacious results with the nickel-base and cobalt-base superalloys. The superalloys will be understood to be those strong, hightemperature materials which find particular utility in the very demanding environments such as gas turbine engines. Representative of these superalloys are those identified in the industry as follows:

Alloy: Composition (percent by weight) IN 10 Cr, 15 Co, 4.5 Ti, 5.5 A1, 3 Mo, .17 C, .75 V, .075 Zr, .015

B, balance Ni. MAR-M200 9' Cr, 10 Co, 2 Ti, 5 A1, 12.5 W, .15 C, 1 Nb, .05 Zr, .015 B,

balance Ni. WI 52 21 Cr, 1.75 Fe, 11W, 2(Nb+Ta),

.45 C, balance Co. MAR-M302 21.5 Cr, 1 Fe, 10 W, 9Ta, .85 C,

.25 Zr, balance Co.

The characteristic of the typical superalloy is its basis as a nickel-chromium or cobalt-chromium solid solution with the additions usually aluminium, titanium and/or refractory metals for solution strengthening, and carbon, boron and zirconium to promote creep-rupture ductility. Taken as a class, the superalloys exhibit relatively good oxidation resistance at the temperatures associated with the hot section of a jet engine. However, since a compromise has normally been made in the alloy composition to achieve the best balance between strength and oxidation resistance as well as other factors, it is the usual practice to coat certain of the components formed from these superalloys to improve their oxidation, sulfidation, erosion and thermal shock resistance, and thus to extend their operating lives.

The Fe-CnAl-Y alloys, as formulated to the prior art chemistry, when applied as a coating to superalloy turbine components, have proved unsatisfactory. While the short term performance of the coating is good, there is a progressive deterioration thereof with time at elevated temperature.

It has now been discovered that an alloy of the composition, by weight, 20-50 percent chromium, 10-20 percent aluminum, 0.03-2 percent yttrium or a rare earth, such as lanthanum or scandium, balance essentially iron, will not only maintain the short term oxidation resistance but will provide long duration protection as well to those engine components to which it is applied. Studies revealed that the conventional alloys when utilized as coatings, rapidly diffused into the base metal depleting the aluminum level in the coating to a point Whereat the protective oxide layer could not be reestablished as the oxide was eroded away in the high velocity gas flow. Usually no stable oxide is formed at coating compositions below about 3-8 weight percent aluminum. Only when the aluminum content of the coating was raised to a minimum of about 10 percent was satisfactory long term coating performance attained. Coincidently, improved coating performance was attained with relatively high chromium contents. In general, the minimum quantities of the elements chromium, aluminum, and yttrium or rare earth are necessary to establish the desired oxidation resistance in the coating while the maximum quantities are an incident of the physical properties such as strength, melting point and oxide adherence.

The yttrium rare earth addition appears to lend stability to the protective oxide. As the best balance between components in the coating composition, the formulation, 25- 29 weight percent chromium, 12-14 weight percent aluminum, 0.6-0.9 percent yttrium, balance iron, is preferred.

In coating the nickel-base and cobalt-base turbine blades and vanes, the surfaces to be coated are first thoroughly cleaned free of all dirt, grease and other objectionable foreign matter followed by conditioning by means of abrasive blasting. The coating is achieved by vapor deposition from a molten pool of the coating material held in a vacuum chamber at torr or better. The melt chemistry in the preferred process is of the following composition:

Carbon max .02 Chromium 26-28 Aluminum 12.5-13.5 Yttrium 0.65-0.75 Phosphorus max .01 Sulfur max .01 Oxygen max .01 Nitrogen max .005 Hydrogen max .005 Other elements, total max 0.5 Iron Remainder Parts are preheated to 1750 F.:50 for 5-6 minutes before deposition is initiated and this temperature is maintained throughout the coating operation. Deposition time varies somewhat but is controlled to obtain the preferred coating thickness of .003-.005 inch. Subsequent cooling to below 1000 F. is accomplished in a non-oxidizing atmosphere at a rate equivalent to air cooling. Following the coating step, the parts are heat treated for 4 hours at 1900 F.i25 in vacuum.

The articles are then dry glass bead peened using .007- 011 inch diameter beads with an intensity equivalent to N. Further details relative to the significance of this working process are set forth in the copending application entitled Method for Coating the Superalloys, Ser. No. 731,649, previously mentioned. In general, the peening is conducted in accordance with the previsions of the processing specification AMS 2430. The parts are then heated to 1975 F.i in dry argon, dry hydrogen or vacuum; held at heat for 4 hours; and cooled in the protective atmosphere at a rate equivalent to air cooling.

The blades and vanes so processed exhibit a coating thickness, excluding diffused zone, of .O03-.005 inch. The diffused zone for the nickel alloys is .001-.002 inch and for the cobalt alloys .0005-.0015 inch.

While the present invention has been described in connection with certain preferred embodiments, these will be understood to be illustrative only. Those modifications to the invention evident to those skilled in the art from the teachings herein will, in the true spirit of the invention, be embraced wthin the scope of the appended claims.

What is claimed is:

1. A composite comprising:

a substrate formed from a nickel-base or cobalt-base superalloy; and

a coating thereon which consists essentially of, by

weight, 20-50 percent chromium, 10-20 percent aluminum, 0.02-2 percent selected from the group consisting of yttrium and the rare earth elements, balance iron.

2. A composite comprising:

a substance formed from a nickel-base or cobalt-base superalloy; and

a coating thereon which consists essentially of, by

weight, 20-50 percent chromium, 10-20 percent aluminum, 0.03-2 percent yttrium, balance iron.

3. A composite for gas turbine engine use comprising:

a substrate formed from a nickel-base or cobalt-base superalloy; and

a coating thereon which consists essentially of, by

weight, 25-29 percent chromium, 12-14 percent aluminum, 0.6-0.9 percent yttrium, balance iron.

4. A composite according to claim 3 wherein:

the coating thickness is 0003-0005 inch.

References Cited UNITED STATES PATENTS 2,105,293 1/1938 Godecke -126 2,946,676 7/1960 Brennan 75124 2,955,937 10/1960 McGutry 75-176 3,027,252 3/1962 McGurty 75-124 3,113,991 12/1963 Kleber 75126 3,298,826 1/1967 Wukusick.

HYLAND BIZOT, Primary Examiner US. Cl. X.R.

222 3? UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3,542,530 Dated November 24, 1970 Frank Pv Talboom, Jr. et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

[- Column 4, line 16 002 should appear as 0.03.

Column 4, line 20 substance should appear as substrate.

TIM-:15 Am; main Tr E 197! FEB. 9,1971

4m mm W J mm 1:. J I I. omission of Patent

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2105293 *Jan 11, 1934Jan 11, 1938Paulin Georges AugusteConvertible body for vehicles, and particularly for motor vehicles
US2946676 *Apr 29, 1957Jul 26, 1960Union Carbide CorpFerrochromium-aluminum alloy
US2955937 *Jan 21, 1958Oct 11, 1960Calkins Vincent POxidation resistant chromium alloy
US3027252 *Sep 29, 1959Mar 27, 1962Gen ElectricOxidation resistant iron-chromium alloy
US3113991 *Aug 18, 1959Dec 10, 1963Nuclear Corp Of AmericaMethod of tagging bulk materials
US3298826 *Apr 6, 1964Jan 17, 1967Wukusick Carl SEmbrittlement-resistant iron-chromium-aluminum-yttrium alloys
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3814447 *Nov 2, 1972Jun 4, 1974Ramsey CorpSealing element for use in internal combustion engines
US3869779 *Jan 24, 1974Mar 11, 1975NasaDuplex aluminized coatings
US3890456 *Aug 6, 1973Jun 17, 1975United Aircraft CorpProcess of coating a gas turbine engine alloy substrate
US3957454 *Nov 15, 1974May 18, 1976General Electric CompanyCoated article
US3964877 *Aug 22, 1975Jun 22, 1976General Electric CompanyPorous high temperature seal abradable member
US4005989 *Jan 13, 1976Feb 1, 1977United Technologies CorporationCoated superalloy article
US4246323 *Sep 11, 1979Jan 20, 1981United Technologies CorporationPlasma sprayed MCrAlY coating
US4275090 *Oct 15, 1979Jun 23, 1981United Technologies CorporationProcess for carbon bearing MCrAlY coating
US4275124 *Oct 15, 1979Jun 23, 1981United Technologies CorporationCarbon bearing MCrAlY coating
US4284688 *Dec 3, 1979Aug 18, 1981Bbc Brown, Boveri & Company LimitedMulti-layer, high-temperature corrosion protection coating
US4346137 *Dec 19, 1979Aug 24, 1982United Technologies CorporationHigh temperature fatigue oxidation resistant coating on superalloy substrate
US4514469 *Sep 10, 1981Apr 30, 1985United Technologies CorporationPeened overlay coatings
US4615865 *Jul 12, 1983Oct 7, 1986United Technologies CorporationOverlay coatings with high yttrium contents
US4711665 *Jul 26, 1985Dec 8, 1987Pennsylvania Research CorporationOxidation resistant alloy
US4889589 *Apr 11, 1988Dec 26, 1989United Technologies CorporationGaseous removal of ceramic coatings
US5015502 *Nov 8, 1989May 14, 1991Allied-Signal Inc.Ceramic thermal barrier coating with alumina interlayer
US5180698 *Apr 25, 1989Jan 19, 1993Merzhanov Alexandr GMethod of preparing refractory chromium-containing material
US5277936 *Nov 19, 1987Jan 11, 1994United Technologies CorporationOxide containing MCrAlY-type overlay coatings
US5716720 *Mar 21, 1995Feb 10, 1998Howmet CorporationThermal barrier coating system with intermediate phase bondcoat
US5824423 *Feb 7, 1996Oct 20, 1998N.V. InterturbineThermal barrier coating system and methods
US5856027 *Mar 31, 1997Jan 5, 1999Howmet Research CorporationThermal barrier coating system with intermediate phase bondcoat
US7455913Jan 10, 2006Nov 25, 2008United Technologies CorporationThermal barrier coating compositions, processes for applying same and articles coated with same
US7579087Jan 10, 2006Aug 25, 2009United Technologies CorporationThermal barrier coating compositions, processes for applying same and articles coated with same
US7622195Jan 10, 2006Nov 24, 2009United Technologies CorporationThermal barrier coating compositions, processes for applying same and articles coated with same
US7879459Jun 27, 2007Feb 1, 2011United Technologies CorporationMetallic alloy composition and protective coating
US8007899Aug 30, 2011United Technologies CorporationSegmented abradable coatings and process(es) for applying the same
US8182881Dec 24, 2008May 22, 2012United Technologies CorporationMethods for reducing stress when applying coatings, processes for applying the same and their coated articles
US8529999Aug 24, 2009Sep 10, 2013United Technologies CorporationThermal barrier coating application processes
US8708646Jan 23, 2009Apr 29, 2014Siemens AktiengesellschaftMCrAlY alloy, methods to produce a MCrAlY layer and a honeycomb seal
US8802199Dec 31, 2009Aug 12, 2014United Technologies CorporationMethod for microstructure control of ceramic thermal spray coating
US8808852Jul 11, 2007Aug 19, 2014United Technologies CorporationProcess for controlling fatigue debit of a coated article
US20070160873 *Jan 10, 2006Jul 12, 2007United Technologies CorporationThermal barrier coating compositions, processes for applying same and articles coated with same
US20070207328 *Mar 1, 2006Sep 6, 2007United Technologies CorporationHigh density thermal barrier coating
US20070231589 *Apr 4, 2006Oct 4, 2007United Technologies CorporationThermal barrier coatings and processes for applying same
US20080113217 *Jan 10, 2006May 15, 2008United Technologies CorporationThermal barrier coating compositions, processes for applying same and articles coated with same
US20080113218 *Jan 10, 2006May 15, 2008United Technologies CorporationThermal barrier coating compositions, processes for applying same and articles coated with same
US20080166489 *Aug 4, 2005Jul 10, 2008United Technologies CorporationMethod for microstructure control of ceramic thermal spray coating
US20090004503 *Jun 27, 2007Jan 1, 2009Melvin FrelingMetallic alloy composition and protective coating
US20090308733 *Dec 17, 2009United Technologies CorporationThermal Barrier Coating Compositions, Processes for Applying Same and Articles Coated with Same
US20100047075 *Nov 2, 2009Feb 25, 2010United Technologies CorporationThermal Barrier Coating Compositions, Processes for Applying Same and Articles Coated with Same
US20100098923 *Oct 5, 2006Apr 22, 2010United Technologies CorporationSegmented abradable coatings and process (ES) for applying the same
US20100151230 *Jul 11, 2007Jun 17, 2010United Technologies CorporationProcess for controlling fatigue debit of a coated article
US20100159149 *Dec 24, 2008Jun 24, 2010United Technologies CorporationApparatus for reducing stress when applying coatings, processes for applying the same and their coated articles
US20100196663 *Apr 9, 2010Aug 5, 2010United Technologies CorporationSegmented Abradable Coatings and Process(es) for Applying the Same
US20100209733 *Oct 7, 2008Aug 19, 2010Man Turbo AgHot Gas-Guided Component of a Turbomachine
US20100260613 *Dec 22, 2006Oct 14, 2010United Technologies CorporationProcess for preventing the formation of secondary reaction zone in susceptible articles, and articles manufactured using same
US20110101619 *Jan 23, 2009May 5, 2011David FairbournA MCrAlY Alloy, Methods to Produce a MCrAlY Layer and a Honeycomb Seal
US20120126485 *Aug 27, 2009May 24, 2012David FairbournHoneycomb Seal And Method To Produce It
USRE33876 *Oct 10, 1989Apr 7, 1992United Technologies CorporationThermal barrier coating for nickel and cobalt base super alloys
DE2319673A1 *Apr 18, 1973Nov 22, 1973Lummus CoVerfahren zum erzeugen eines schutzueberzuges von metallen
DE2830851A1 *Jul 13, 1978Jan 18, 1979Fiat SpaVerfahren zur bildung von metalldiffusionsschutzueberzuegen
DE3229285A1 *Aug 5, 1982Mar 24, 1983United Technologies CorpBelagzusammensetzung zur herstellung eines schutzbelags auf substraten aus einer superlegierung
DE3229293A1 *Aug 5, 1982Mar 24, 1983United Technologies CorpDeckbelaege fuer superlegierungen
EP0074918A2 *Sep 8, 1982Mar 23, 1983United Technologies CorporationMethod for simultaneous peening and smoothing
EP0780484A1Dec 13, 1996Jun 25, 1997General Electric CompanyThermal barrier coated articles and method for coating
EP1752553A2Aug 4, 2006Feb 14, 2007United Technologies CorporationMethod for microstructure control of ceramic thermal spray coating
EP1829984A1Mar 1, 2007Sep 5, 2007United Technologies CorporationHigh Density Thermal Barrier Coating
EP1939326A2Dec 11, 2007Jul 2, 2008United Technologies CorporationProcess for preventing the formation of secondary reaction zone in susceptible articles, and articles manufactured using same
EP2014786A1Jul 9, 2008Jan 14, 2009United Technologies CorporationProcess for controlling fatigue debit of a coated article
EP2098606A1 *Mar 4, 2008Sep 9, 2009Siemens AktiengesellschaftA MCrAlY alloy, methods to produce a MCrAlY layer and a honeycomb seal
EP2204465A2Sep 21, 2009Jul 7, 2010United Technologies CorporationApparatus for reducing stress when applying coatings, processes for applying the same and their coated articles
WO1990005120A1 *Apr 25, 1989May 17, 1990Institut Strukturnoi Makrokinetiki Akademii Nauk SssrMethod of obtaining chromium-containing refractory material
WO2009049796A1 *Oct 7, 2008Apr 23, 2009Man Turbo AgHot gas-guided component of a turbomachine
WO2009109414A1 *Jan 23, 2009Sep 11, 2009Siemens AktiengesellschaftA MCrAlY ALLOY, METHODS TO PRODUCE A MCrAlY LAYER AND A HONEYCOMB SEAL
Classifications
U.S. Classification428/667, 428/678, 420/40, 428/926, 420/583
International ClassificationC23C30/00, C23C14/16, C22C38/18
Cooperative ClassificationC23C14/16, C22C38/18, Y10S428/926, C23C30/00
European ClassificationC23C14/16, C22C38/18, C23C30/00