US3694255A - Method for coating heat resistant alloys - Google Patents

Method for coating heat resistant alloys Download PDF

Info

Publication number
US3694255A
US3694255A US43082A US3694255DA US3694255A US 3694255 A US3694255 A US 3694255A US 43082 A US43082 A US 43082A US 3694255D A US3694255D A US 3694255DA US 3694255 A US3694255 A US 3694255A
Authority
US
United States
Prior art keywords
pack
alloy
coating
aluminum
chromium
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.)
Expired - Lifetime
Application number
US43082A
Other languages
English (en)
Inventor
Harry W Brill-Edwards
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.)
Chromalloy American Corp
Original Assignee
Chromalloy American 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 Chromalloy American Corp filed Critical Chromalloy American Corp
Application granted granted Critical
Publication of US3694255A publication Critical patent/US3694255A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/28—Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes
    • C23C10/34—Embedding in a powder mixture, i.e. pack cementation
    • C23C10/36—Embedding in a powder mixture, i.e. pack cementation only one element being diffused
    • C23C10/38—Chromising
    • C23C10/40—Chromising of ferrous surfaces
    • C23C10/42—Chromising of ferrous surfaces in the presence of volatile transport additives, e.g. halogenated substances

Definitions

  • chromium which has a lower propensity to oxidize than an oxidation resistant solute metal in the alloy (e.g. aluminum), and then subjecting the alloy article to pack cementation at an elevated temperature while maintaining the oxygen in the pack at a partial pressure below the oxygen threshold level at which the alloy is subject to internal oxidation.
  • an oxidation resistant solute metal in the alloy e.g. aluminum
  • This invention relates to the diffusion coating of metals, such as heat resistant superalloys, and, in particular, to a process for producing an adherent oxidation and suldation resistant coating comprising chromium and aluminum on superalloy substrates while avoiding internal oxidation within the coating.
  • the invention is particularly applicable to high nickel alloys for high temperature applications in, for example, jet and other thermal engines or gas turbines.
  • the nickel or cobalt superalloys may exhibit physical properties within a desirable range for a variety of uses, particularly when subjected in use to extremely high temperatures, the combination of such properties as oxidation resistance and/or erosion or sulfidation resistance at the surface of such alloys, the resistance to thermal shock and the strength characteristics may be less than desired for prolonged severe use.
  • increased amounts of hardeners such as aluminum and/or titanium, were added to certain nickel-base alloys in order to assure stiffness at the high temperature levels.
  • the hardeners increased in amount, it was not unusual to decrease the amount of chromium in such alloys in order to increase high temperature strength.
  • a case in point is a nickel-base alloy referred to in the trade by the designation B-l900 which comprises by weight about 0.1% carbon, 8% chromium, 10% cobalt, ⁇ 6% molybdenum, 1% titanium, 6% aluminum, 0.015% boron, 0.1% zirconium, 4% tantalum and the balance essentially nickel.
  • B-l900 nickel-base alloy
  • a disadvantage of such alloys is that with decreased amounts of chromium, the resistance to oxidation and suldation is generally adversely affected. Usually, 18% chromium or better is required for suliidation resistance.
  • a chromium-free alloy which has shown particular promise as a jet engine or gas turbine component and which exhibits excellent stress-rupture properties at ternperatures as high as 2200" F. and above is an alloy comprising about 18% molybdenum, about 8% aluminum and the balance essentially nickel.
  • this alloy does not have the desirable oxidation and/or sulfidation resistance and, therefore, its application in the gas turbine eld has been severely limited due to the lack of a coating.
  • the alloy contains gamma prime (7') precipitate (Ni3Al). The absence of chromium stabilizes the fine precipitate of the gamma prime to relatively high temperatures, for example, to above 2200 F. as compared to 1950 F.
  • Such gamma prime strengthened alloys as the alloy bearing the designation B-1900 referred to hereinabove.
  • the alloy also contains a small amount of carbon, e.g. 0.03% carbon by Weight, which appears as molybdenum carbide precipitated throughout the matrix.
  • the superior mechanical properties are attributed to its lack of chromium, to its high molybdenum content, and to the relative absence of grain boundary carbides.
  • this alloy must be used in the coated condition in order to withstand oxidation and sulfidation attack in gas turbine environments.
  • a duplex chromium/aluminum coating on this alloy in conventional cementation packs were not successful due to internal oxidation occurring within the coating during the initial chromizing step.
  • the procedure usually employed was to embed the metal article to be coated in a dry powder pack, including an inert mineral filler (e.g. powdered alumina), a source of chromium to be diffusion coated and a source of a vaporizable halogen material.
  • a typical pack is one containing by weight about 25% chromium, about 1A% of a halide energizer (e.g. ammonium iodide) and the balance alumina.
  • the metal article As embedded in such a pack contained within a metal container or retort, the seams of which are sealed by a fusible material, such as low melting silicate glass, to prevent excessive escape of the diffusing material during heating and inhibit introduction of air in the pack during the thermal cycle, the metal article is heated in a known manner to a diffusion temperature and held at temperature for a number of hours to cause diffusion coating of the chromium into the substrate of the article. Thereafter, the chromized article is aluminized, using another pack cementation procedure.
  • a fusible material such as low melting silicate glass
  • the initial chromizing step applied to the high molybdenum-aluminum nickel-base superalloy resulted in localized internal oxidation within the chromium affected zones.
  • This oxidation manifested itself inthe form of angular inclusions of aluminum oxide particles within the chromium rich solid solution region of the coating, the size of the inclusions increasing with increasing coating temperature.
  • the internal oxidation concentrated near the surface of the coating in which the aluminum concentration had been reduced by dissolution of the chromium from about 8% aluminum to a level below 3% by weight.
  • the internal oxidation was not observed to penetrate through the coating diffusion ones into the base metal where the aluminum level approached 8% by weight.
  • the low chromium, nickel-base superalloys were observed to exhibit the same phenomenon, such as alloys of the type referred to herein as B-l900.
  • the aluminum oxide inclusions have an adverse effect on the properties of the alloy in that the presence of inclusions tends to reduce the resistance of the coating to impact and, moreover, the aluminum oxide/coating matrix interfaces introduce regions susceptible to rapid corrosion attack.
  • Another object is to provide a pack cementation method for coating the substrate of an article made of a heat resistant superalloy in which the heat resistant alloy contains a solute metal (e.g. aluminum) in an amount having a higher propensity to oxidize than the primary coating metal (e.g. chromium) in the cementation pack and the solvent metal of the alloy, while substantially avoiding internal oxidation within the coating.
  • a solute metal e.g. aluminum
  • the primary coating metal e.g. chromium
  • a still further object is to provide a multi-step pack cementation process forl producing a multiple oxidation and sullidation corrosion resistant coating on superalloys substantially free from internal oxidation near the interface of the coating.
  • the invention also provides a process for coating a molybdenum-aluminum alloy containing major amounts of nickel.
  • FIGS. 1 and 2 are reproductions of photomicrographs taken at 400 times magnification showing the internal oxidation which occurs within a coating produced by a method outside of the invention
  • FIG. 3 is a reproduction of a photomicrograph taken at 400 times magnification showing the same alloy composition with no internal oxidation within the coating produced in accordance with the invention
  • FIG. 4 is illustrative of a photomicrograph taken at 400 times magnification showing the extent to which internal oxidation occurs when the pack cementation process of the invention is carried out in a retort without an adequate seal;
  • FIG. 5 is a reproduction of a photomicrograph taken at 400 times magnification showing a coating produced using a pack composition outside the invention depicting nickel aluminide build-up and the attendant entrapment of alumina particles from the pack;
  • FIG. 6 is a reproduction of a photomicrograph taken at 400 times magm'cation showing the various phases making up a duplex coating produced in accordance with the invention while avoiding the formation of inclusions of aluminum oxide in the coating.
  • the invention is directed to a method for coating by pack cementation the substrate of an article formed of a heat resistant Ialloy in which the heat resistant alloy contains a solute metal in amounts having a relatively higher propensity to oxidize than the coating metal in the cementation pack and the solvent metal of the base alloy such that normally an internally oxidized structure is produced within the coating during pack cementation comprising an oxide dispersion of the oxidizable solute metal due to the presence of oxygen in the pack.
  • the improvement resides in embedding the alloy article containing the solute metal in a cementation pack comprising a coating metal having a lower propensity to oxide than the solute metal, and then carrying out the cementation process at an elevated coating temperature while maintaining the oxygen in the pack at a partial pressure below the oxygen threshhold level at which the alloy is subject to internal oxidation.
  • the solute metal in the alloy to be coated includes those metals the oxides of which have a negative free energy of formation of at least about 115,000 calories per gram atom of oxygen at about 25 C., and generally at least about 125,000 calories, e.g. 133,000 calories or higher.
  • solute metals normally present in superalloys are aluminum, titanium, and the like.
  • the invention is particularly applicable to heat resistant alloys of the nickel-base type containing aluminum yand/or titanium hardeners.
  • the invention is further applicable to pack cementation systems in which chromium is the initial coating metal and in which the solute metal in the alloy is aluminum.
  • a preferred method of maintaining the oxygen in the pack to below the threshold level is to add to the pack an effective amount of a getter whose propensity to oxidize is at least equal to that of the solute metal in the alloy to be coated.
  • a getter found particularly satisfactory is aluminum powder in effective amounts ranging up to about 1.25%, the amount of aluminum being advantageously less than that amount which interferes with the diiusion of chromium into the substrate and which tends to cause the attendant entrapment of pack material in the coating.
  • nickel aluminide may tend to form on the substrate which then inhibits diffusion of chromium therein.
  • a range of aluminum content by weight in the pack found particularly advantageously is about 0.25% to 0.75%.
  • the invention is applicable to the coating of a broad range of alloy compositions, such as those containing by weight up to about 30% of a metal from the group consisting of Cr, Mo and W, the total of these metals not exceeding about 40%, with the Cr content preferably not exceeding about 10% or 15%, up to about 10% by weight of a metal from the group consisting of Cb and Ta; up to about 1% C; up to about 10% by weight of a metal from the group consisting of Ti and Al, the total amount of these metals not exceeding about 12%; up to about 2% Mn; up to about 2% Si; up to about 0.1% B; up to about 1% Zr; and the balance at least about 50% nickel.
  • the iron group metals Fe and/or Co may be substituted for at least part of the nickel.
  • the alloy may contain up to 20% or more of cobalt.
  • the invention is particularly applicable to the coating of nickel-molybdenum-aluminum alloys containing by weight up to about 30% molybdenum (more advantageously about 10% to 25%), about 0.5 to 10% aluminum (more advantageously about 4% to 10%), up to about 0.1% carbon (e.g. 0.03%), and the balance essentially nickel.
  • a specific example of the alloy (known commercially as NX-188) is one containing approximately 17.5% molybdenum, approximately 7.75% aluminum, approximately 0.03% carbon, and the balance essentially nickel.
  • the oxygen threshold level should desirably not exceed 4 parts per million of the gas in the pack.
  • a chromizing pack which is particularly advantageous in carrying out the invention is one containing by weight about 5% to 15% chromium, about 0.25% to 0.75% aluminum, about 3% to 5% nickel and the balance essentially an inert diluent, such as refractory oxide, for example, alumina.
  • the pack has mixed with it an effective amount of a halide energizer, e.g. one-quarter percent.
  • the function of nickel in the above pack is to maintain the aluminum potential below a level that causes nickel aluminide to form on the alloy, while, at the same time, not suppressing the chromium transfer rate.
  • halide energizers examples include ammonium iodide, ammonium bromide, ammonium bifluoride, and the like.
  • a typical multistep process for coating heat resistant alloys may comprise, providing a first cementation pack containing a first coating metal (e.g. chromium) having a lower propensity to oxidize than the solute metal in the alloy (e.g. aluminum) to be coated, embedding the heat resistant alloy in the pack, carrying out a first cementation process at an elevated coating temperature while maintaining the oxygen in the pack at a partial pressure below the oxygen threshold level at which the alloy is subject to internal oxidation, whereby the alloy is coated with the rst coating metal while substantially avoiding internal oxidation, embedding the coated alloy in a second cementation pack containing at least one other coating metal (e.g. aluminum) and carrying out the second cementation at an elevated temperature.
  • a first coating metal e.g. chromium
  • a cementation pack which may be employed in the second coating step for transferring, for example, aluminum as the second coating material comprises about 5% to 40% of a buffering metal (e.g. chromium), about 1.25% to 20% aluminum and the balance essentially an inert diluent containing a small but effective amount of a halide energizer, the amount of aluminum at the higher range being correlated to the higher range of the buffering metal (e.g. chromium), with the lower range of aluminum being correlated to the lower range of the buffering metal.
  • the buffering metal aids in controlling the transfer and the deposition of the aluminum. Examples of other buffering metals are nickel, iron and cobalt.
  • the pack be prepared by first pre-reacting it at an elevated temperature, for example 18501 F. to 2200 F. for from 1 to 20 hours. The pre-reacted pack is then re-energized by mixing it with a small but effective amount of ammonium halide, e.g., one-quarter percent ammonium bromide, and the article to be coated then pack chromized at about 1900 F. to 2200 F. for times up to about 50 hours, e.g. 30 hours at 2000 F. for the alloy NX-188.
  • an elevated temperature for example 18501 F. to 2200 F. for from 1 to 20 hours.
  • ammonium halide e.g., one-quarter percent ammonium bromide
  • a typical chromizing pack (the first coat) is one prepared from about by weight of -20 +40 mesh-Cr, 4% by -weight of minus 200 mesh Ni, or 1% by weight of aluminum powder of size of about minus 325 mesh, one-quarter percent NH4Br and the balance -14 +28 mesh A1203.
  • a typical aluminizing pack (the second coat) is 22% by weight of -20 +40i mesh Cr, 8% by weight of aluminum powder of size of about minus 325 mesh, one-quarter percent of NHgFHF and the balance A1203 of -14 +28 mesh.
  • the coating with the latter pack is carried out at 1700 F. for 20 hours. Broadly speaking, the temperature may range from about 1600 F. to 2000 F. for up to about 50 hours, e.g. 10 to 30 hours.
  • the final coating on the metal substrate comprises an outer layer of nickel aluminide phase with dispersed alpha chromium particles (70% Cr-20% Mo). Moving further inward from the outer layer, the composition of the white precipitated phases changes from chromium-rich behind the aluminzed zone to molybdenum-rich near the substrate.
  • the chromized layer is not suicient by itself to provide the necessary protection against hot corrosion.
  • a chromized layer (5 mil thick) produced in accordance with the invention on an alloy substrate comprising about 17.5 Mo, about 7.75% Al and the balance essentially Ni exhibited good resistance to sullidation.
  • oxidation exposure at 2200 F. caused sufficient vaporization of the oxidized chromium surface thereby reducing the life over which the coating afforded sulfidation resistance.
  • the chromized substrate was aluminzed to form nickel aluminide, the resulting duplex coating exhibited excellent oxidation and sullidation resistance.
  • a chromizing pack is rst prepared by mixing -by weight 15% of -20 +40 mesh chromium powder, 4% minus 200 mesh nickel powder, 1% minus 325 mesh aluminum powder, NH4Br and the balance essentially -14 +28 mesh A1203. The mixed powders are pre-reacted at 2l00 F. for 20 hours and then re-energized with NH4Br.
  • the pre-reacted re-energized pack is placed in a retort and the element embedded in the pack.
  • the retort is sealed with a low melting silicate glass composition and the retort then heated in a muie furnace to a temperature of 2100 F. and held at temperature for about 30 hours.
  • the retort is thereafter cooled to room temperature and the chromized element (referred to as Test No. 1) is metallographically examined for internal oxidation.
  • Example 1 conrm that unless the partial pressure of oxygen in the pack is maintained low enough, internal oxidation will occur during chromizing. This is also true even if inadequate quantities of the getter are present or if the seal is inadequate.
  • Test A was conducted on the Ni-Mo-Al alloy using a chromizing pack containing 15% chromium, 4% nickel with 3% aluminum as the getter under a good retort seal.
  • the metal substrate was processed at a ternperature of 2100 F. for 30 hours and the metallographic structure shown in FIG. 5 was obtained.
  • a nickel aluminide layer was formed having entrapped therein alumina particles from the pack. Because nickel aluminide was deposited on the substrate, the chromium transfer was suppressed. This type of coating does not provide adequate hot corrosion protection of the alloy at elevated temperatures ranging up to about 2200 F.
  • EXAMPLE 2 An alloy referred to by the designation B-1900 may similarly be chromized in accordance with the invention While avoiding internal oxidation.
  • This alloy contains nominally 0.1% carbon, 8% chromium, 10% cobalt, 6% molybdenum, 1% titanium, 6% aluminum, 0.015% boron, 0.1% zirconium, 4% tantalum and the balance essentially nickel.
  • an element of the alloy is embedded in a prereacted pack contained in a sealed retort comprising by weight about of -20 +40 mesh chromium powder, about 3% minus 200 mesh nickel powder, about 0.5% minus 325 mesh aluminum, about NH4I and the balance A1203 of about -14 +28 mesh.
  • the mixed powders are prereacted at 2l00 F. for 20 hours and then re-energized with 1A of NH4I.
  • the pre-reacted re-energized pack is placed in a retort and the element of the alloy embedded in the pack, the retort -being then sealed.
  • the assembly is heated in a furnace to a temperature of about 1900 F. for 30 hours and thereafter cooled to room temperature to produce a chromized element substantially free from internal oxidation.
  • EXAMPLE 3 An element of an alloy referred to by the designation TRW-6A and comprising about 0.13% carbon, 6.1% chromium, 7.5% cobalt, 2% molybdenum, 5.8% tungsten, 0.5% columbiurn, 1% titanium, 5.4% aluminum, 0.02% boron, 0.13% zirconium, 9% tantalum, 0.4% hafnium, 0.14% rhenium and the balance essentially nickel is chromized similarly as in Example l, except that the pre-reacted pack contains about 5% chromium, 3% nickel, 0.35% aluminum, NH4FHF and the balance alumina. The assembly of the retort containing the pack with the embedded element therein is then sealed and heated to about 1925 F. and held at temperature for about 30 hours and thereafter cooled to room temperature to provide a chromized element substantially free from internal oxidation.
  • TRW-6A An element of an alloy referred to by the designation TRW-6A and comprising about 0.13% carbon,
  • the alloy of nickel-molybdenum-aluminum coated in Example 1 (Test No. 1) in accordance with the invention may be aluminized by using a pre-reacted pack composition comprising by weight 22% of -20 +40 mesh chromium powder as a buiering metal, 8% of minus 325 mesh aluminum powder, 1t% ammonium bifluoride (NH4FHF) and the balance an inert refractory oxide, e.g. -14 +28 mesh A1203.
  • a pre-reacted pack composition comprising by weight 22% of -20 +40 mesh chromium powder as a buiering metal, 8% of minus 325 mesh aluminum powder, 1t% ammonium bifluoride (NH4FHF) and the balance an inert refractory oxide, e.g. -14 +28 mesh A1203.
  • a duplex coating is produced comprising a surface layer of nickel aluminide (NiAl) containing a dispersion of alpha chromium (Mo) particles.
  • the sub-surface coating comprises a nickelchromium solid solution containing aluminum in solid solution, the amount of aluminum remaining substantially constant at about 7.5 to 8% at the aluminide interface to the nominal 7.5% or 8% at the base alloy interface.
  • Molybdenum rich phases are formed in the chromium solid solution adjacent the substrate.
  • the surface layer is enriched in nickel aluminide, the layer below and adjacent it comprising a layer of chromium rich solid solution.
  • a layer of molybdenum rich phases is interposed between the chromium rich solid solution and the metal substrate comprised of the nickel-molybdenum-aluminum alloy containing approximately 17.5% molybdenum, approximately 7.75% aluminum and the balance essentially nickel.
  • the foregoing layers are metallurgically bonded to each other and to the substrate.
  • the temperature which may be employed to aluminize the chromized alloy may range from about 1600 F. to 2000 F. for up to about 50 hours, e.g. l0 to 30 hours.
  • a method of chromizing by pack cementation in a sealed container the substrate of an article formed of a heat resistant gamma prime strengthened nickel-base alloy with up to about 10% chromium by weight, a gamma prime forming solute metal in an amount having a greater propensity to oxidize than the chromium coating metal in said pack and the balance essentially nickel, while greatly inhibiting the formation of an internally oxidized structure in said coating which comprises,
  • the alloy article in a cementation pack comprising chromium, an inert diluent, a small but effective amount of a halide energizer, and an effective amount of a getter whose propensity to oxidize is at least equal to that of the solute metal in the alloy, the getter being one Whose negative free energy of formation of the oxide at about 25 C. is at least about 115,000 calories per gram atom of oxygen:
  • the amount of the getter ranging up to about 1.25% by Weight of the pack and being less than that amount which interferes with the diffusion of chromium into the substrate and which tends to cause entrapment of pack material in the coating, and then carrying out the cementation in a sealed container at an elevated chromizing temperature,
  • the heat resistant alloy of the article contains by'weight up to about 30% of at least one metal from the group consisting of Cr, Mo and W, the total of these metals not exceeding about 40%, the chromium content of the alloy not exceeding about 10%, up to about 10% by weight of a metal from the group consisting of Cb and Ta; up to about 1% C, up to about 10% by weight of a solute metal from the group consisting of Ti and Al, the total amount of these metals not exceeding about 12%; up to about 20% Co; up to about 2% Mn, up to about 2% Si; up to about 0.1% B; up to about 1% Zr; and the balance at least about 50% nickel, and wherein the getter is aluminum.
  • said alloy article in said cementation pack comprising chromium, an inert diluent, a small but effective amount of a halide energizer, and an effective amount of a getter whose propensity to oxidize is at least equal to that of the solute metal in the alloy, the getter being one whose negative free energy of formation of the oxide at about 25 C. is at least about 115,000 calories per gram atom of 0X- YgeD,
  • the amount of the getter ranging up to about 1.25%

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Electroplating And Plating Baths Therefor (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Heat Treatment Of Steel (AREA)
US43082A 1970-06-03 1970-06-03 Method for coating heat resistant alloys Expired - Lifetime US3694255A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US4308270A 1970-06-03 1970-06-03

Publications (1)

Publication Number Publication Date
US3694255A true US3694255A (en) 1972-09-26

Family

ID=21925406

Family Applications (1)

Application Number Title Priority Date Filing Date
US43082A Expired - Lifetime US3694255A (en) 1970-06-03 1970-06-03 Method for coating heat resistant alloys

Country Status (9)

Country Link
US (1) US3694255A (enExample)
JP (1) JPS5248096B1 (enExample)
CA (1) CA923769A (enExample)
CH (1) CH542288A (enExample)
DE (1) DE2126479C3 (enExample)
FR (1) FR2093999B1 (enExample)
GB (1) GB1328458A (enExample)
IL (1) IL36817A (enExample)
SE (2) SE392485B (enExample)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3758233A (en) * 1972-01-17 1973-09-11 Gen Motors Corp Vibration damping coatings
US4122673A (en) * 1973-09-28 1978-10-31 J. Eberspacher Internal combustion engine with afterburning and catalytic reaction in a supercharger turbine casing
US4148936A (en) * 1976-12-23 1979-04-10 General Electric Company Method for diffusion coating an Fe-Ni base alloy with chromium
US4467016A (en) * 1981-02-26 1984-08-21 Alloy Surfaces Company, Inc. Aluminized chromized steel
US4497610A (en) * 1982-03-23 1985-02-05 Rolls-Royce Limited Shroud assembly for a gas turbine engine
US5928725A (en) * 1997-07-18 1999-07-27 Chromalloy Gas Turbine Corporation Method and apparatus for gas phase coating complex internal surfaces of hollow articles

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4352840A (en) * 1980-11-17 1982-10-05 Turbine Metal Technology, Inc. Interdispersed phase coatings method
FR2502186A1 (fr) * 1981-03-17 1982-09-24 Onera (Off Nat Aerospatiale) Procede de protection de piece en super-alliage contre la corrosion a chaud et pieces protegees correspondantes
GB2167773A (en) * 1984-11-29 1986-06-04 Secr Defence Improvements in or relating to coating processes

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3758233A (en) * 1972-01-17 1973-09-11 Gen Motors Corp Vibration damping coatings
US4122673A (en) * 1973-09-28 1978-10-31 J. Eberspacher Internal combustion engine with afterburning and catalytic reaction in a supercharger turbine casing
US4148936A (en) * 1976-12-23 1979-04-10 General Electric Company Method for diffusion coating an Fe-Ni base alloy with chromium
US4467016A (en) * 1981-02-26 1984-08-21 Alloy Surfaces Company, Inc. Aluminized chromized steel
US4497610A (en) * 1982-03-23 1985-02-05 Rolls-Royce Limited Shroud assembly for a gas turbine engine
US5928725A (en) * 1997-07-18 1999-07-27 Chromalloy Gas Turbine Corporation Method and apparatus for gas phase coating complex internal surfaces of hollow articles

Also Published As

Publication number Publication date
FR2093999A1 (enExample) 1972-02-04
SE375117B (enExample) 1975-04-07
IL36817A (en) 1973-10-25
DE2126479A1 (de) 1971-12-09
GB1328458A (en) 1973-08-30
IL36817A0 (en) 1971-07-28
DE2126479B2 (de) 1978-09-14
DE2126479C3 (de) 1979-05-23
CH542288A (fr) 1973-09-30
JPS5248096B1 (enExample) 1977-12-07
CA923769A (en) 1973-04-03
FR2093999B1 (enExample) 1974-03-22
SE392485B (sv) 1977-03-28

Similar Documents

Publication Publication Date Title
US3801353A (en) Method for coating heat resistant alloys
US4080486A (en) Coating system for superalloys
US3978251A (en) Aluminide coatings
US4070507A (en) Platinum-rhodium-containing high temperature alloy coating method
US3961098A (en) Coated article and method and material of coating
US5077141A (en) High strength nickel base single crystal alloys having enhanced solid solution strength and methods for making same
US3415672A (en) Method of co-depositing titanium and aluminum on surfaces of nickel, iron and cobalt
US3951642A (en) Metallic coating powder containing Al and Hf
EP0267143B1 (en) Method for applying aluminide coatings to superalloys
US3958047A (en) Diffusion treatment of metal
JP6205128B2 (ja) セル状シールの製造方法
Lindblad A review of the behavior of aluminide-coated superalloys
US4024294A (en) Protective coatings for superalloys
US4142023A (en) Method for forming a single-phase nickel aluminide coating on a nickel-base superalloy substrate
RU2362832C2 (ru) Покрытия для турбинных лопаток
US3957454A (en) Coated article
US3979534A (en) Protective coatings for dispersion strengthened nickel-chromium/alloys
US3694255A (en) Method for coating heat resistant alloys
JPH01257A (ja) 耐酸化性かつ耐高温腐食性ニッケル基合金被覆材並びにそれを用いた複合製品
US4084025A (en) Process of applying protective aluminum coatings for non-super-strength nickel-chromium alloys
US3996021A (en) Metallic coated article with improved resistance to high temperature environmental conditions
US3290126A (en) Protectively coated nickel or cobalt articles and process of making
US4528215A (en) Diffusion aluminizing of cobalt-base superalloys
US3073015A (en) Diffusion coating of metals
US3764373A (en) Diffusion coating of metals

Legal Events

Date Code Title Description
AS Assignment

Owner name: CHROMALLOY GAS TURBINE CORPORATION, A DE. CORP., N

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CHROMALLOY AMERICAN CORPORATION;REEL/FRAME:004862/0635

Effective date: 19880311

Owner name: CHROMALLOY GAS TURBINE CORPORATION, BLAISDELL ROAD

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CHROMALLOY AMERICAN CORPORATION;REEL/FRAME:004862/0635

Effective date: 19880311