US20060057416A1 - Article having a surface protected by a silicon-containing diffusion coating - Google Patents
Article having a surface protected by a silicon-containing diffusion coating Download PDFInfo
- Publication number
- US20060057416A1 US20060057416A1 US11/109,160 US10916005A US2006057416A1 US 20060057416 A1 US20060057416 A1 US 20060057416A1 US 10916005 A US10916005 A US 10916005A US 2006057416 A1 US2006057416 A1 US 2006057416A1
- Authority
- US
- United States
- Prior art keywords
- percent
- article
- silicon
- component
- protective layer
- 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
Links
- 229910052710 silicon Inorganic materials 0.000 title claims abstract description 53
- 239000010703 silicon Substances 0.000 title claims abstract description 53
- 238000000576 coating method Methods 0.000 title abstract description 51
- 239000011248 coating agent Substances 0.000 title abstract description 47
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 title abstract description 40
- 238000009792 diffusion process Methods 0.000 title description 2
- 239000000203 mixture Substances 0.000 claims abstract description 57
- 229910000601 superalloy Inorganic materials 0.000 claims abstract description 24
- 239000000758 substrate Substances 0.000 claims description 24
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 18
- 239000011241 protective layer Substances 0.000 claims description 17
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 16
- 229910052782 aluminium Inorganic materials 0.000 claims description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 9
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 9
- 229910052799 carbon Inorganic materials 0.000 claims description 9
- 229910052759 nickel Inorganic materials 0.000 claims description 9
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 8
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 8
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 8
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 8
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 8
- 229910052796 boron Inorganic materials 0.000 claims description 8
- 229910052804 chromium Inorganic materials 0.000 claims description 8
- 239000011651 chromium Substances 0.000 claims description 8
- 239000010941 cobalt Substances 0.000 claims description 8
- 229910017052 cobalt Inorganic materials 0.000 claims description 8
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 8
- 229910052742 iron Inorganic materials 0.000 claims description 8
- 229910052750 molybdenum Inorganic materials 0.000 claims description 8
- 239000011733 molybdenum Substances 0.000 claims description 8
- 229910052758 niobium Inorganic materials 0.000 claims description 8
- 239000010955 niobium Substances 0.000 claims description 8
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims description 8
- 239000010936 titanium Substances 0.000 claims description 8
- 229910052719 titanium Inorganic materials 0.000 claims description 8
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 8
- 229910052721 tungsten Inorganic materials 0.000 claims description 8
- 239000010937 tungsten Substances 0.000 claims description 8
- 229910052726 zirconium Inorganic materials 0.000 claims description 8
- 229910052715 tantalum Inorganic materials 0.000 claims description 4
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims description 4
- 239000012190 activator Substances 0.000 abstract description 12
- 150000004820 halides Chemical class 0.000 abstract description 11
- 238000010438 heat treatment Methods 0.000 abstract description 9
- 239000000843 powder Substances 0.000 abstract description 9
- 238000004891 communication Methods 0.000 abstract description 3
- 239000002585 base Substances 0.000 description 21
- 239000007789 gas Substances 0.000 description 21
- 238000013459 approach Methods 0.000 description 17
- 239000011253 protective coating Substances 0.000 description 16
- 239000000567 combustion gas Substances 0.000 description 9
- 238000005260 corrosion Methods 0.000 description 7
- 238000012545 processing Methods 0.000 description 7
- 229910045601 alloy Inorganic materials 0.000 description 6
- 239000000956 alloy Substances 0.000 description 6
- 239000010953 base metal Substances 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 5
- 230000008021 deposition Effects 0.000 description 5
- -1 ammonium halide Chemical class 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 4
- DDFHBQSCUXNBSA-UHFFFAOYSA-N 5-(5-carboxythiophen-2-yl)thiophene-2-carboxylic acid Chemical compound S1C(C(=O)O)=CC=C1C1=CC=C(C(O)=O)S1 DDFHBQSCUXNBSA-UHFFFAOYSA-N 0.000 description 3
- 230000002411 adverse Effects 0.000 description 3
- NLKNQRATVPKPDG-UHFFFAOYSA-M potassium iodide Chemical compound [K+].[I-] NLKNQRATVPKPDG-UHFFFAOYSA-M 0.000 description 3
- 239000011863 silicon-based powder Substances 0.000 description 3
- FVAUCKIRQBBSSJ-UHFFFAOYSA-M sodium iodide Chemical compound [Na+].[I-] FVAUCKIRQBBSSJ-UHFFFAOYSA-M 0.000 description 3
- 230000000930 thermomechanical effect Effects 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 238000012856 packing Methods 0.000 description 2
- IOLCXVTUBQKXJR-UHFFFAOYSA-M potassium bromide Chemical compound [K+].[Br-] IOLCXVTUBQKXJR-UHFFFAOYSA-M 0.000 description 2
- NROKBHXJSPEDAR-UHFFFAOYSA-M potassium fluoride Chemical compound [F-].[K+] NROKBHXJSPEDAR-UHFFFAOYSA-M 0.000 description 2
- 230000003716 rejuvenation Effects 0.000 description 2
- ABTOQLMXBSRXSM-UHFFFAOYSA-N silicon tetrafluoride Chemical group F[Si](F)(F)F ABTOQLMXBSRXSM-UHFFFAOYSA-N 0.000 description 2
- JHJLBTNAGRQEKS-UHFFFAOYSA-M sodium bromide Chemical compound [Na+].[Br-] JHJLBTNAGRQEKS-UHFFFAOYSA-M 0.000 description 2
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 2
- 239000002344 surface layer Substances 0.000 description 2
- 238000011282 treatment Methods 0.000 description 2
- IRPGOXJVTQTAAN-UHFFFAOYSA-N 2,2,3,3,3-pentafluoropropanal Chemical compound FC(F)(F)C(F)(F)C=O IRPGOXJVTQTAAN-UHFFFAOYSA-N 0.000 description 1
- KLZUFWVZNOTSEM-UHFFFAOYSA-K Aluminum fluoride Inorganic materials F[Al](F)F KLZUFWVZNOTSEM-UHFFFAOYSA-K 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910004074 SiF6 Inorganic materials 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 239000001103 potassium chloride Substances 0.000 description 1
- 235000011164 potassium chloride Nutrition 0.000 description 1
- 239000011698 potassium fluoride Substances 0.000 description 1
- 235000003270 potassium fluoride Nutrition 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 235000002639 sodium chloride Nutrition 0.000 description 1
- 239000011775 sodium fluoride Substances 0.000 description 1
- 235000013024 sodium fluoride Nutrition 0.000 description 1
- 235000009518 sodium iodide Nutrition 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
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
- C23C10/44—Siliconising
- C23C10/46—Siliconising of ferrous surfaces
-
- 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
- C23C10/06—Solid state diffusion of only metal elements or silicon into metallic material surfaces using gases
- C23C10/08—Solid state diffusion of only metal elements or silicon into metallic material surfaces using gases only one element being diffused
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/12—All metal or with adjacent metals
- Y10T428/12458—All metal or with adjacent metals having composition, density, or hardness gradient
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/12—All metal or with adjacent metals
- Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
- Y10T428/12674—Ge- or Si-base component
Definitions
- This invention relates to the protection of a surface with a coating, and more particularly to the protection of a nickel-base superalloy gas turbine component with a silicon-containing coating.
- the turbine disks and seal components operated at a sufficiently low temperature that hot corrosion was not a major concern.
- some of the components such as the turbine disk and some of the seal components, are operated at a sufficiently high temperature that they are subjected to hot corrosion during operation.
- the corrodant is introduced into the turbine section of the engine in the hot combustion gases.
- the corrodant typically includes alkaline sulfate deposits that may have carbon as well.
- Nickel-base superalloys are used as the materials of construction of some types of turbine disks and seal components. In service, the nickel-base superalloys are exposed to hot corrosion in the intermediate temperature range of about 1000° F. to about 1500° F. The compositions of the nickel-base superalloys are selected to achieve the required mechanical properties in service. However, the superalloys that have the desired mechanical properties are not sufficiently resistant to hot-corrosion damage. The hot-corrosion damage, if it becomes sufficiently severe, may cause the superalloy component to fail prematurely.
- Environmentally resistant coatings are known for use with nickel-base superalloys operated at higher temperatures.
- Aluminum-containing diffusional and overlay coatings that oxidize to produce a protective aluminum oxide scale are widely used.
- these coatings are typically not suitable for use on wrought gas turbine components operated in the temperature range of about 1000° F. to about 1500° F., because they require higher deposition temperatures that adversely affect the mechanical properties of the heat-treated wrought nickel-base superalloys.
- the present invention fulfills this need, and further provides related advantages.
- the present approach provides a method for protecting a surface of an article. It is particularly useful for protecting a component of a gas turbine engine that is operated in a temperature range of from about 1000° 20 F. to about 1500° F. and potentially subject to hot corrosion from the hot combustion gases, such as gas turbine disks and some seal components.
- the present approach protects the surface of the article, is compatible with the thermomechanical processing of wrought nickel-base superalloys used to manufacture the articles, and is compatible with achieving and maintaining the mechanical properties required in the article.
- the coating approach is not limited by line of sight access to the surface that is to be protected. It is also environmentally friendly and readily used in commercial operations.
- a method for protecting a surface of an article comprises the steps of providing the article having the surface thereon, and thereafter coating the surface with a silicon-containing coating.
- the coating is accomplished by preparing a coating mixture having silicon, a halide activator, and an oxide powder, positioning the surface of the article in gaseous communication with the coating mixture, and heating the surface of the article and the coating mixture to a coating temperature of from about 1150° F. to about 1500° F., typically in an oven.
- the surface is contacted to the coating mixture, as by packing the coating mixture around and in contact with the surface.
- the coating mixture preferably has from about 2 to about 10 percent by weight of silicon powder, from about 0.1 to about 0.5 percent by weight of a halide activator, and the balance aluminum oxide powder.
- the coating is preferably performed in an inert atmosphere or hydrogen.
- the heating time is determined by the desired thickness of the protective layer, but is typically on the order of from about 2 to about 8 hours.
- the article is preferably made of a nickel-base superalloy, and most preferably a wrought nickel-base superalloy.
- Examples of such articles are components of a gas turbine engine, such as turbine disks and seals.
- the surface of the article may be mechanically worked before it is coated.
- the resulting article is preferably a component of a gas turbine engine having a nickel-base superalloy substrate composition, with a protective layer at the surface of the component.
- the protective layer comprises a mixture of silicon and elements from the substrate composition interdiffused with the silicon.
- the protective layer consists essentially of a mixture of silicon and elements from the substrate composition interdiffused with the silicon.
- the protected article is preferably operated in a gas turbine at an operating temperature of from about 1000° F. to about 1500° F. and contacted by hot combustion gas.
- the chemical reaction between the silicon and the halide activator produces a silicon-containing gas.
- An example is silicon fluoride in the case of a fluoride-containing activator.
- the silicon-containing gas is transported to the component, which serves as a substrate for the deposition of the silicon-containing gas.
- the silicon-containing gas Upon contacting the surface of the substrate, the silicon-containing gas decomposes to deposit silicon on the substrate. Because the reaction and the vapor-phase transport are performed at elevated temperatures, the silicon interdiffuses with elements from the substrate composition to produce a silicon-rich surface layer.
- the silicon-rich surface layer protects the article against corrosion by the corrosive components of the hot combustion gas.
- FIG. 1 is a perspective view of a protected component of a gas turbine engine
- FIG. 2 is a block flow diagram of an approach for protecting the component
- FIG. 3 is a schematic sectional view of a coating apparatus with the article packed in the coating mixture.
- FIG. 4 is a schematic sectional view of the protected component of FIG. 1 , taken on line 4 - 4 .
- FIG. 1 illustrates one such article 20 , a turbine disk 22 having an article surface 24 .
- Other components include, for example, seals and compressor components.
- the present approach is not limited to the production of these articles, however.
- FIG. 2 depicts a preferred approach for protecting the surface 24 of the article 20 .
- the article 20 having the article surface 24 thereon is provided, step 30 .
- the article 20 is furnished in substantially its final size and shape, and underlying base-metal composition.
- the surface protection treatment to be described subsequently alters the dimensions of the article only very slightly.
- the article 20 is preferably made of a nickel-base alloy as the base metal, and is most preferably made of a nickel-base superalloy.
- a nickel-base alloy is a composition of matter having more nickel than any other element.
- a nickel-base superalloy is a nickel-base alloy that is hardenable by the precipitation of gamma prime or a related phase.
- a presently preferred nickel-base superalloy that is to be protected by the present approach is ReneTM 88DT, having a nominal composition, in weight percent, of 13 percent cobalt, 16 percent chromium, 4 percent molybdenum, 3.7 percent titanium, 2.1 percent aluminum, 4 percent tungsten, 0.75 percent niobium, 0.015 percent boron, 0.03 percent zirconium, and 0.03 percent carbon, up to about 0.5 percent iron, balance nickel and minor amounts of other elements.
- alloy ME3 having a nominal composition, in weight percent, of about 20.6 percent cobalt, about 13.0 percent chromium, about 3.4 percent aluminum, about 3.7 percent titanium, about 2.4 percent tantalum, about 0.90 percent niobium, about 2.10 percent tungsten, about 3.80 percent molybdenum, about 0.05 percent carbon, about 0.025 percent boron, about 0.05 percent zirconium, up to about 0.5 percent iron, balance nickel and minor amounts of other elements.
- These alloys are presented by way of example, and the use of the present invention is not so limited.
- the nickel-base superalloy is desirably a wrought nickel-base superalloy, which is cast and then mechanically worked, usually by thermomechanical working at elevated temperature such as by forging, to reach the shape of the article 20 . It may also be heat treated prior to working, at intermediate points in the working process, and after working. The details of the working and heat treating are known in the art for each alloy.
- the surface 24 of the article 20 may be mechanically worked or otherwise processed as a final stage of the providing step 30 .
- the article surface 24 may be shot peened to induce a desired stress state into the article surface 24 . It may optionally be grit blasted or vapor honed.
- the working, heat treating, mechanical working, and other processing produce a desired structure and stress state at the surface 24 and in the microstructure of the article 20 .
- This structure and stress state may not be disturbed or altered by heating the article 20 to a temperature of greater than about 1500° F. in subsequent processing, or the mechanical performance under service conditions of the article 20 will be adversely affected.
- the article surface 24 is thereafter coated with a silicon-containing coating, step 32 .
- the coating operation 32 first includes preparing a coating mixture of silicon, a halide activator, and an oxide powder, step 34 .
- the silicon is preferably furnished as silicon powder of any operable size, most preferably ⁇ 100 mesh.
- the halide activator is of any operable type. Operable halide activators include, for example, ammonium fluoride, ammonium chloride, sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, aluminum fluoride, and aluminum chloride, or mixtures thereof.
- the halide activator is an ammonium halide or an aluminum halide.
- the oxide powder is inert in the coating operation and serves to slow the coating process and prevent agglomeration of the powders that would prevent access of the coating vapor to the surface 24 .
- the oxide powder is preferably aluminum oxide (alumina, or Al 2 O 3 ). Any operable oxide powder size may be used, but a preferred size is ⁇ 325 mesh.
- a preferred composition of the coating mixture is from about 2 to about 10 percent by weight of silicon powder, from about 0.1 to about 0.5 percent by weight of a halide activator, and the balance aluminum oxide powder.
- the surface 24 of the article 20 is positioned in gaseous communication with the coating mixture, step 36 .
- Any operable approach may be used, but the presently preferred approach, illustrated in FIG. 3 , is to pack the coating mixture 50 in contact with the surface 24 of the article, as by packing the entire article 20 in the coating mixture 50 .
- the article 20 may be placed into a container 52 , and the solid coating mixture 50 is poured into the container 52 to surround and immerse the article 20 .
- the surface 24 of the article 20 and the coating mixture 50 are thereafter heated to a coating temperature of from about 1150° F. to about 1500° F., step 38 . If the coating temperature is lower than about 1150° F., the rate of coating is too slow to be commercially feasible. If the coating temperature is greater than about 1500° F., the stress state, structure, and/or microstructure of the underlying article 20 are adversely affected.
- the preferred approach is to heat the surface 24 of the article 20 and the coating mixture 50 in an oven 54 , see FIG. 3 .
- the oven 54 may be of any operable type, but is represented as an electrically heated oven with electrical heating coils 56 .
- the heating 38 is preferably performed in an inert-gas (e.g., argon) or hydrogen-reducing atmosphere, supplied by a gas source 58 .
- the heating causes the halide activator to react with the silicon to produce a gaseous form.
- the halide activator is ammonium fluoride
- the ammonium fluoride decomposes to produce fluoride ions.
- the fluoride ions react with the silicon to produce a silicon-bearing gas such as gaseous silicon fluoride (SiF 6 or a related form).
- the silicon-bearing gas diffuses to the surface 24 of the article 20 .
- the silicon-bearing gas decomposes to deposit silicon upon the surface 24 .
- the article 20 thereby serves as a substrate 60 for the deposition of the silicon and thence the protective coating 62 , as shown in FIG. 4 .
- the silicon is initially deposited in elemental form. However, because the deposition is performed at elevated temperature, the deposited silicon interdiffuses with the base metal of the substrate composition, which is a nickel-base superalloy in the preferred embodiment.
- the protective coating 62 is therefore a diffusion coating whose composition is a gradient composition extending through the protective coating 62 . At the surface 24 , the protective coating 62 has its greatest percentage silicon content and lowest percentage content of base-metal elements from the substrate 60 .
- the portion of the protective coating 62 at and nearest the surface 24 may be substantially completely pure silicon, if the silicon deposition in step 38 is continued for a sufficiently long time. With increasing distance below the surface 24 , the percentage of silicon in the coating is reduced, and the percentage of the base-metal elements of the substrate 60 increases until it reaches 100 percent at the greatest depth 64 of the protective coating 62 . Optionally but not preferably at the present time, other elements may be co-deposited with the silicon to become part of the protective coating 62 .
- the heating step 38 is continued for a time sufficient to produce the protective coating 62 of a desired thickness.
- a preferred coating temperature range of from about 1250° F. to about 1400° F. for a time of from about 2 to about 8 hours has been found sufficient for most applications of interest.
- a heating step 38 of about 5 hours at a coating temperature of about 1400° F. produces a protective coating 62 about 0 . 0007 inch thick.
- the coating temperature may, however, range as low as 1150° F. and as high as 1500° F., as discussed earlier.
- the article 20 with the protective coating 62 thereon is final processed, step 40 .
- the final processing may include, for example, thermal treatments, final machining of uncoated portions, and cleaning.
- the article 20 with the protective coating 62 in place is operated in service, step 42 .
- the article 20 is operated at an operating temperature of from about 1000° F. to about 1500° F. and contacted by hot combustion gas for an extended period of time.
- the protective coating 62 may be restored and rejuvenated by recoating, step 44 .
- the protective coating 62 may be restored and rejuvenated by recoating, step 44 .
- the as-deposited protective coating 62 is “self-healing”, as any excess silicon in the protective coating 62 may interdiffuse with the substrate 60 during service.
- the protective coating 62 becomes thinner and in some places may be lost entirely.
- step 32 is repeated after the article 20 is cleaned, and all service-produced residue removed.
- Step 40 may optionally be repeated as necessary.
- the article 20 may then be returned to service, step 42 . Subsequent recoatings/rejuvenations are permissible.
Abstract
A surface of an article is protected by coating the surface with a silicon-containing coating by preparing a coating mixture of silicon, a halide activator, and an oxide powder, positioning the surface of the article in gaseous communication with the coating mixture, and heating the surface of the article and the coating mixture to a coating temperature of from about 1150° F. to about 1500° F. The article is preferably a component of a gas turbine engine made of a nickel-base superalloy.
Description
- This invention relates to the protection of a surface with a coating, and more particularly to the protection of a nickel-base superalloy gas turbine component with a silicon-containing coating.
- In a basic form of an aircraft gas turbine (jet) engine, air is drawn into the front of the engine, compressed by a shaft-mounted compressor, and mixed with fuel. The mixture is burned, and the hot combustion gas is passed through a turbine mounted on the same shaft. The turbine includes a turbine disk (sometimes termed the “rotor”), upon which turbine blades are mounded. The flow of combustion gas turns the turbine by impingement against an airfoil section of the turbine blades, which turns the shaft and provides power to the compressor. Seals prevent the leakage of hot combustion gas around the turbine. After passing through the turbine, the hot combustion gas flows from the back of the engine, driving it and the aircraft forward.
- In prior generations of aircraft gas turbine engines, the turbine disks and seal components operated at a sufficiently low temperature that hot corrosion was not a major concern. In current and advanced gas turbine engines, however, some of the components, such as the turbine disk and some of the seal components, are operated at a sufficiently high temperature that they are subjected to hot corrosion during operation. The corrodant is introduced into the turbine section of the engine in the hot combustion gases. The corrodant typically includes alkaline sulfate deposits that may have carbon as well.
- Nickel-base superalloys are used as the materials of construction of some types of turbine disks and seal components. In service, the nickel-base superalloys are exposed to hot corrosion in the intermediate temperature range of about 1000° F. to about 1500° F. The compositions of the nickel-base superalloys are selected to achieve the required mechanical properties in service. However, the superalloys that have the desired mechanical properties are not sufficiently resistant to hot-corrosion damage. The hot-corrosion damage, if it becomes sufficiently severe, may cause the superalloy component to fail prematurely.
- Environmentally resistant coatings are known for use with nickel-base superalloys operated at higher temperatures. Aluminum-containing diffusional and overlay coatings that oxidize to produce a protective aluminum oxide scale are widely used. However, these coatings are typically not suitable for use on wrought gas turbine components operated in the temperature range of about 1000° F. to about 1500° F., because they require higher deposition temperatures that adversely affect the mechanical properties of the heat-treated wrought nickel-base superalloys.
- There is a need for an improved approach to the protection of nickel-base superalloys and other materials operated in a corrosive environment in the temperature range of about 1000° F. to about 1500° F. The new approach must be compatible with the processing of the component. The present invention fulfills this need, and further provides related advantages.
- The present approach provides a method for protecting a surface of an article. It is particularly useful for protecting a component of a gas turbine engine that is operated in a temperature range of from about 1000°20 F. to about 1500° F. and potentially subject to hot corrosion from the hot combustion gases, such as gas turbine disks and some seal components. The present approach protects the surface of the article, is compatible with the thermomechanical processing of wrought nickel-base superalloys used to manufacture the articles, and is compatible with achieving and maintaining the mechanical properties required in the article. The coating approach is not limited by line of sight access to the surface that is to be protected. It is also environmentally friendly and readily used in commercial operations.
- A method for protecting a surface of an article comprises the steps of providing the article having the surface thereon, and thereafter coating the surface with a silicon-containing coating. The coating is accomplished by preparing a coating mixture having silicon, a halide activator, and an oxide powder, positioning the surface of the article in gaseous communication with the coating mixture, and heating the surface of the article and the coating mixture to a coating temperature of from about 1150° F. to about 1500° F., typically in an oven. Most preferably, the surface is contacted to the coating mixture, as by packing the coating mixture around and in contact with the surface.
- The coating mixture preferably has from about 2 to about 10 percent by weight of silicon powder, from about 0.1 to about 0.5 percent by weight of a halide activator, and the balance aluminum oxide powder. The coating is preferably performed in an inert atmosphere or hydrogen. The heating time is determined by the desired thickness of the protective layer, but is typically on the order of from about 2 to about 8 hours.
- The article is preferably made of a nickel-base superalloy, and most preferably a wrought nickel-base superalloy. Examples of such articles are components of a gas turbine engine, such as turbine disks and seals. The surface of the article may be mechanically worked before it is coated.
- The resulting article is preferably a component of a gas turbine engine having a nickel-base superalloy substrate composition, with a protective layer at the surface of the component. The protective layer comprises a mixture of silicon and elements from the substrate composition interdiffused with the silicon. Most preferably, the protective layer consists essentially of a mixture of silicon and elements from the substrate composition interdiffused with the silicon.
- The protected article is preferably operated in a gas turbine at an operating temperature of from about 1000° F. to about 1500° F. and contacted by hot combustion gas.
- When the coating mixture is heated during the coating step, the chemical reaction between the silicon and the halide activator produces a silicon-containing gas. An example is silicon fluoride in the case of a fluoride-containing activator. The silicon-containing gas is transported to the component, which serves as a substrate for the deposition of the silicon-containing gas. Upon contacting the surface of the substrate, the silicon-containing gas decomposes to deposit silicon on the substrate. Because the reaction and the vapor-phase transport are performed at elevated temperatures, the silicon interdiffuses with elements from the substrate composition to produce a silicon-rich surface layer. The silicon-rich surface layer protects the article against corrosion by the corrosive components of the hot combustion gas.
- The present protection approach, which does not require that the component be heated during processing to a temperature above its normal service operating temperature, is fully compatible with the thermomechanical and other processing treatments of wrought nickel-base superalloys that are used in the preferred components such as gas turbine disks and seals. Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. The scope of the invention is not, however, limited to this preferred embodiment.
-
FIG. 1 is a perspective view of a protected component of a gas turbine engine; -
FIG. 2 is a block flow diagram of an approach for protecting the component; -
FIG. 3 is a schematic sectional view of a coating apparatus with the article packed in the coating mixture; and -
FIG. 4 is a schematic sectional view of the protected component ofFIG. 1 , taken on line 4-4. - The present approach may be used to process a wide variety of physical forms of workpieces to produce a wide variety of
final articles 20. Components of gas turbine engines are of particular interest.FIG. 1 illustrates onesuch article 20, aturbine disk 22 having anarticle surface 24. Other components include, for example, seals and compressor components. The present approach is not limited to the production of these articles, however. -
FIG. 2 depicts a preferred approach for protecting thesurface 24 of thearticle 20. Thearticle 20 having thearticle surface 24 thereon is provided,step 30. Thearticle 20 is furnished in substantially its final size and shape, and underlying base-metal composition. The surface protection treatment to be described subsequently alters the dimensions of the article only very slightly. - The
article 20 is preferably made of a nickel-base alloy as the base metal, and is most preferably made of a nickel-base superalloy. A nickel-base alloy is a composition of matter having more nickel than any other element. A nickel-base superalloy is a nickel-base alloy that is hardenable by the precipitation of gamma prime or a related phase. A presently preferred nickel-base superalloy that is to be protected by the present approach is Rene™ 88DT, having a nominal composition, in weight percent, of 13 percent cobalt, 16 percent chromium, 4 percent molybdenum, 3.7 percent titanium, 2.1 percent aluminum, 4 percent tungsten, 0.75 percent niobium, 0.015 percent boron, 0.03 percent zirconium, and 0.03 percent carbon, up to about 0.5 percent iron, balance nickel and minor amounts of other elements. Another example is alloy ME3, having a nominal composition, in weight percent, of about 20.6 percent cobalt, about 13.0 percent chromium, about 3.4 percent aluminum, about 3.7 percent titanium, about 2.4 percent tantalum, about 0.90 percent niobium, about 2.10 percent tungsten, about 3.80 percent molybdenum, about 0.05 percent carbon, about 0.025 percent boron, about 0.05 percent zirconium, up to about 0.5 percent iron, balance nickel and minor amounts of other elements. These alloys are presented by way of example, and the use of the present invention is not so limited. - The nickel-base superalloy is desirably a wrought nickel-base superalloy, which is cast and then mechanically worked, usually by thermomechanical working at elevated temperature such as by forging, to reach the shape of the
article 20. It may also be heat treated prior to working, at intermediate points in the working process, and after working. The details of the working and heat treating are known in the art for each alloy. - The
surface 24 of thearticle 20 may be mechanically worked or otherwise processed as a final stage of the providingstep 30. For example, thearticle surface 24 may be shot peened to induce a desired stress state into thearticle surface 24. It may optionally be grit blasted or vapor honed. - The working, heat treating, mechanical working, and other processing produce a desired structure and stress state at the
surface 24 and in the microstructure of thearticle 20. This structure and stress state may not be disturbed or altered by heating thearticle 20 to a temperature of greater than about 1500° F. in subsequent processing, or the mechanical performance under service conditions of thearticle 20 will be adversely affected. - The
article surface 24 is thereafter coated with a silicon-containing coating,step 32. Thecoating operation 32 first includes preparing a coating mixture of silicon, a halide activator, and an oxide powder,step 34. The silicon is preferably furnished as silicon powder of any operable size, most preferably −100 mesh. The halide activator is of any operable type. Operable halide activators include, for example, ammonium fluoride, ammonium chloride, sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide, aluminum fluoride, and aluminum chloride, or mixtures thereof. Most preferably, the halide activator is an ammonium halide or an aluminum halide. The oxide powder is inert in the coating operation and serves to slow the coating process and prevent agglomeration of the powders that would prevent access of the coating vapor to thesurface 24. The oxide powder is preferably aluminum oxide (alumina, or Al2O3). Any operable oxide powder size may be used, but a preferred size is −325 mesh. - A preferred composition of the coating mixture is from about 2 to about 10 percent by weight of silicon powder, from about 0.1 to about 0.5 percent by weight of a halide activator, and the balance aluminum oxide powder.
- The
surface 24 of thearticle 20 is positioned in gaseous communication with the coating mixture,step 36. Any operable approach may be used, but the presently preferred approach, illustrated inFIG. 3 , is to pack thecoating mixture 50 in contact with thesurface 24 of the article, as by packing theentire article 20 in thecoating mixture 50. For example and as illustrated, thearticle 20 may be placed into acontainer 52, and thesolid coating mixture 50 is poured into thecontainer 52 to surround and immerse thearticle 20. - The
surface 24 of thearticle 20 and thecoating mixture 50 are thereafter heated to a coating temperature of from about 1150° F. to about 1500° F.,step 38. If the coating temperature is lower than about 1150° F., the rate of coating is too slow to be commercially feasible. If the coating temperature is greater than about 1500° F., the stress state, structure, and/or microstructure of theunderlying article 20 are adversely affected. - The preferred approach is to heat the
surface 24 of thearticle 20 and thecoating mixture 50 in an oven 54, seeFIG. 3 . The oven 54 may be of any operable type, but is represented as an electrically heated oven with electrical heating coils 56. Theheating 38 is preferably performed in an inert-gas (e.g., argon) or hydrogen-reducing atmosphere, supplied by agas source 58. - The heating causes the halide activator to react with the silicon to produce a gaseous form. For example, if the halide activator is ammonium fluoride, the ammonium fluoride decomposes to produce fluoride ions. The fluoride ions react with the silicon to produce a silicon-bearing gas such as gaseous silicon fluoride (SiF6 or a related form). The silicon-bearing gas diffuses to the
surface 24 of thearticle 20. Upon contacting thesurface 24, the silicon-bearing gas decomposes to deposit silicon upon thesurface 24. - The
article 20 thereby serves as asubstrate 60 for the deposition of the silicon and thence theprotective coating 62, as shown inFIG. 4 . The silicon is initially deposited in elemental form. However, because the deposition is performed at elevated temperature, the deposited silicon interdiffuses with the base metal of the substrate composition, which is a nickel-base superalloy in the preferred embodiment. Theprotective coating 62 is therefore a diffusion coating whose composition is a gradient composition extending through theprotective coating 62. At thesurface 24, theprotective coating 62 has its greatest percentage silicon content and lowest percentage content of base-metal elements from thesubstrate 60. The portion of theprotective coating 62 at and nearest thesurface 24 may be substantially completely pure silicon, if the silicon deposition instep 38 is continued for a sufficiently long time. With increasing distance below thesurface 24, the percentage of silicon in the coating is reduced, and the percentage of the base-metal elements of thesubstrate 60 increases until it reaches 100 percent at the greatest depth 64 of theprotective coating 62. Optionally but not preferably at the present time, other elements may be co-deposited with the silicon to become part of theprotective coating 62. - The
heating step 38 is continued for a time sufficient to produce theprotective coating 62 of a desired thickness. A preferred coating temperature range of from about 1250° F. to about 1400° F. for a time of from about 2 to about 8 hours has been found sufficient for most applications of interest. For example, aheating step 38 of about 5 hours at a coating temperature of about 1400° F. produces aprotective coating 62 about 0.0007 inch thick. The coating temperature may, however, range as low as 1150° F. and as high as 1500° F., as discussed earlier. - After the
coating 32 is complete, thearticle 20 with theprotective coating 62 thereon is final processed,step 40. The final processing may include, for example, thermal treatments, final machining of uncoated portions, and cleaning. - The
article 20 with theprotective coating 62 in place is operated in service,step 42. In the preferred application, thearticle 20 is operated at an operating temperature of from about 1000° F. to about 1500° F. and contacted by hot combustion gas for an extended period of time. - One of the advantages of the present approach is that, after service, the
protective coating 62 may be restored and rejuvenated by recoating,step 44. During service, it is expected that some of theprotective coating 62 would be corroded or eroded away, or otherwise lost. To some extent the as-depositedprotective coating 62 is “self-healing”, as any excess silicon in theprotective coating 62 may interdiffuse with thesubstrate 60 during service. Eventually, however, theprotective coating 62 becomes thinner and in some places may be lost entirely. To perform the recoating,step 32 is repeated after thearticle 20 is cleaned, and all service-produced residue removed.Step 40 may optionally be repeated as necessary. Thearticle 20 may then be returned to service,step 42. Subsequent recoatings/rejuvenations are permissible. - The present approach has been reduced to practice. Flat panel specimens of Rene™ 88DT were coated by the preferred approach discussed above. The coated flat panel specimens and uncoated specimens of Rene™ 88DT were exposed at 1300° F. to a sodium sulfate corrodant mixture and periodically evaluated. The coated specimens had about three times the life of the uncoated specimens.
- Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.
Claims (22)
1-17. (canceled)
18. An article comprising
a component of a gas turbine engine having a nickel-base superalloy substrate composition; and
a protective layer at a surface of the component, wherein the protective layer comprises a mixture of silicon and elements from the substrate composition interdiffused with the silicon.
19. The article of claim 18 , wherein the substrate has a nominal composition, in weight percent, of 13 percent cobalt, 10 percent chromium, 4 percent molybdenum, 3.7 percent titanium, 2.1 percent aluminum, 4 percent tungsten. 0.75 percent niobium, 0.015 percent boron, 0.03 percent zirconium, and 0.03 percent carbon, up to about 0.5 percent iron, balance nickel arid minor amounts of other elements; or has a nominal composition, in weight percent, of about 20.6 percent cobalt, about 13.0 percent chromium, about 3.4 percent aluminum, about 3.7 percent titanium, about 2.4 percent tantalum, about 0.90 percent niobium, about 2.10 percent tungsten, about 3.80 percent molybdenum, about 0.05 percent carbon, about 0.025 percent boron, about 0.05 percent zirconium, up to about 0.5 percent iron, balance nickel and minor amounts of other elements.
20. The article of claim 18 , wherein the protective layer consists essentially of a mixture of silicon and elements from the substrate composition interdiffused with the silicon.
21. (canceled)
22. The article of claim 18 , wherein the component is in a cast-and-worked form.
23. The article of claim 18 , wherein tile surface of the substrate component is mechanically worked.
24. (canceled)
25. The article of claim 18 , wherein the article is a turbine disk, a seal, or a compressor component.
26. An article comprising
a component of a gas turbine engine having a nickel-base superalloy substrate composition In a cast-and-worked form; and
a protective layer at a surface of the component, wherein the protective layer comprises silicon.
27. The article of claim 26 , wherein the substrate has a nominal composition, in weight percent, of 13 percent cobalt, 16 percent chromium, 4 percent molybdenum, 3.7 percent titanium, 2.1 percent aluminum, 4 percent tungsten, 0.75 percent niobium, 0.015 percent boron, 0.03 percent zirconium, and 0.03 percent carbon, up to about 0.5 percent iron, balance nickel and minor amounts of other elements; or has a nominal composition, in weight percent, of about 20.6 percent cobalt, about 13.0 percent chromium, about 3.4 percent aluminum, about 3.7 percent titanium, about 2.4 percent tantalum, about 0.90 percent niobium, about 2.10 percent tungsten, about 3.80 percent molybdenum, about 0.05 percent carbon, about 0.025 percent boron, about 0.05 percent zirconium, up to about 0.5 percent iron, balance nickel and minor amounts of other elements.
28. The article of claim 26 , wherein the protective layer comprises a mixture of silicon and elements from the substrate composition interdiffused with the silicon.
29. (canceled)
30. The article of claim 18 , wherein the protective layer is substantially pure silicon at the surface of the component.
31. The article of claim 26 , wherein the protective layer is substantially pure silicon at the surface of the component.
32. An article comprising
a component having a nickel-base superalloy substrate composition; and
a protective layer at a surface of the component, wherein the protective layer comprises a mixture of silicon and elements from the substrate composition interdiffused with the silicon, and wherein the protective layer has a gradient composition with a greatest percentage of silicon at the surface of the component and a reduced percentage of silicon with increasing distance into the component from the surface of the component.
33. The article of claim 32 , wherein the substrate has a nominal composition, in weight percent, of 13 percent cobalt, 16 percent chromium, 4 percent molybdenum, 3.7 percent titanium, 2.1 percent aluminum, 4 percent tungsten, 0.75 percent niobium, 0.015 percent boron, 0.03 percent zirconium, and 0.03 percent carbon, up to about 0.5 percent iron, balance nickel and minor amounts of other elements; or has a nominal composition, in weight percent, of about 20.6 percent cobalt, about 13.0 percent chromium, about 3.4 percent aluminum, about 3.7 percent titanium, about 2.4 percent tantalum, about 0.90 percent niobium, about 2.10 percent tungsten, about 3.80 percent molybdenum, about 0.05 percent carbon, about 0.025 percent boron, about 0.05 percent zirconium, up to about 0.5 percent iron, balance nickel and minor amounts of other elements.
34. The article of claim 32 , wherein the protective layer consists essentially of a mixture of silicon and elements from the substrate composition interdiffused with the silicon.
35. The article of claim 32 , wherein the component is in a cast-and-worked form.
36. The article of claim 32 , wherein the surface of the component is mechanically worked.
37. The article of claim 32 , wherein the article is a turbine disk, a seal, or a compressor component.
38. The article of claim 32 , wherein the protective layer is substantially pure silicon at the surface of the component.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/109,160 US20060057416A1 (en) | 2002-12-13 | 2005-04-19 | Article having a surface protected by a silicon-containing diffusion coating |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/318,762 US6933012B2 (en) | 2002-12-13 | 2002-12-13 | Method for protecting a surface with a silicon-containing diffusion coating |
US11/109,160 US20060057416A1 (en) | 2002-12-13 | 2005-04-19 | Article having a surface protected by a silicon-containing diffusion coating |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/318,762 Division US6933012B2 (en) | 2002-12-13 | 2002-12-13 | Method for protecting a surface with a silicon-containing diffusion coating |
Publications (1)
Publication Number | Publication Date |
---|---|
US20060057416A1 true US20060057416A1 (en) | 2006-03-16 |
Family
ID=32506456
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/318,762 Expired - Fee Related US6933012B2 (en) | 2002-12-13 | 2002-12-13 | Method for protecting a surface with a silicon-containing diffusion coating |
US11/109,160 Abandoned US20060057416A1 (en) | 2002-12-13 | 2005-04-19 | Article having a surface protected by a silicon-containing diffusion coating |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/318,762 Expired - Fee Related US6933012B2 (en) | 2002-12-13 | 2002-12-13 | Method for protecting a surface with a silicon-containing diffusion coating |
Country Status (1)
Country | Link |
---|---|
US (2) | US6933012B2 (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070141374A1 (en) * | 2005-12-19 | 2007-06-21 | General Electric Company | Environmentally resistant disk |
US7364801B1 (en) | 2006-12-06 | 2008-04-29 | General Electric Company | Turbine component protected with environmental coating |
WO2009064817A1 (en) * | 2007-11-13 | 2009-05-22 | Entelos, Inc. | Simulating patient-specific outcomes |
EP2971243B1 (en) | 2013-03-13 | 2020-02-26 | General Electric Company | Coatings for metallic substrates |
DE102015212511B4 (en) * | 2014-07-24 | 2019-06-06 | Ford Global Technologies, Llc | Method for producing a brake disk and brake disk |
Citations (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3037883A (en) * | 1959-02-18 | 1962-06-05 | Chromalloy Corp | Diffusion coating of non-ferrous metals |
US3073015A (en) * | 1960-05-16 | 1963-01-15 | Chromalloy Corp | Diffusion coating of metals |
US3257230A (en) * | 1964-03-24 | 1966-06-21 | Chromalloy American Corp | Diffusion coating for metals |
US4310574A (en) * | 1980-06-20 | 1982-01-12 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Method of protecting a surface with a silicon-slurry/aluminide coating |
US4369233A (en) * | 1978-07-21 | 1983-01-18 | Elbar B.V., Industrieterrien "Spikweien" | Process to apply a protecting silicon containing coating on specimen produced from superalloys and product |
US4371570A (en) * | 1980-02-11 | 1983-02-01 | United Technologies Corporation | Hot corrosion resistant coatings |
US4500384A (en) * | 1982-02-05 | 1985-02-19 | Chisso Corporation | Process for producing a non-woven fabric of hot-melt-adhered composite fibers |
US5124123A (en) * | 1988-09-26 | 1992-06-23 | General Electric Company | Fatigue crack resistant astroloy type nickel base superalloys and product formed |
US5266360A (en) * | 1991-12-20 | 1993-11-30 | United Technologies Corporation | Inhibiting coke formation by coating gas turbine elements with silica |
US5547770A (en) * | 1992-05-19 | 1996-08-20 | Sermatech International, Inc. | Multiplex aluminide-silicide coating |
US5649280A (en) * | 1996-01-02 | 1997-07-15 | General Electric Company | Method for controlling grain size in Ni-base superalloys |
US5897718A (en) * | 1996-04-24 | 1999-04-27 | Rolls-Royce Plc | Nickel alloy for turbine engine components |
US6126758A (en) * | 1992-09-05 | 2000-10-03 | Sermatech International Inc. | Aluminide-silicide coatings, coating compositions, process for coating and improved coated products |
US6537388B1 (en) * | 1996-08-23 | 2003-03-25 | Alon, Inc. | Surface alloy system conversion for high temperature applications |
US20040221927A1 (en) * | 2002-07-19 | 2004-11-11 | Raymond Edward Lee | Isothermal forging of nickel-base superalloys in air |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1025841A (en) * | 1961-10-17 | 1966-04-14 | Bristol Siddeley Engines Ltd | Improvements in refractory metal articles |
US4500364A (en) * | 1982-04-23 | 1985-02-19 | Exxon Research & Engineering Co. | Method of forming a protective aluminum-silicon coating composition for metal substrates |
GB2167773A (en) * | 1984-11-29 | 1986-06-04 | Secr Defence | Improvements in or relating to coating processes |
JP3458220B2 (en) * | 1995-01-31 | 2003-10-20 | 株式会社アライドマテリアル | Oxidation resistant molybdenum material and method for producing the same |
FR2769852B1 (en) * | 1997-10-21 | 1999-12-03 | Commissariat Energie Atomique | COMPOSITE POWDER, PROCESS FOR PREPARING THE SAME, AND DIFFUSION DEPOSITION METHOD USING THE SAME |
JP2001122681A (en) * | 1999-10-25 | 2001-05-08 | Natl Inst Of Advanced Industrial Science & Technology Meti | Oxidation resistant coating method for non-oxide high temperature material |
-
2002
- 2002-12-13 US US10/318,762 patent/US6933012B2/en not_active Expired - Fee Related
-
2005
- 2005-04-19 US US11/109,160 patent/US20060057416A1/en not_active Abandoned
Patent Citations (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3037883A (en) * | 1959-02-18 | 1962-06-05 | Chromalloy Corp | Diffusion coating of non-ferrous metals |
US3073015A (en) * | 1960-05-16 | 1963-01-15 | Chromalloy Corp | Diffusion coating of metals |
US3257230A (en) * | 1964-03-24 | 1966-06-21 | Chromalloy American Corp | Diffusion coating for metals |
US4369233A (en) * | 1978-07-21 | 1983-01-18 | Elbar B.V., Industrieterrien "Spikweien" | Process to apply a protecting silicon containing coating on specimen produced from superalloys and product |
US4371570A (en) * | 1980-02-11 | 1983-02-01 | United Technologies Corporation | Hot corrosion resistant coatings |
US4310574A (en) * | 1980-06-20 | 1982-01-12 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Method of protecting a surface with a silicon-slurry/aluminide coating |
US4500384A (en) * | 1982-02-05 | 1985-02-19 | Chisso Corporation | Process for producing a non-woven fabric of hot-melt-adhered composite fibers |
US5124123A (en) * | 1988-09-26 | 1992-06-23 | General Electric Company | Fatigue crack resistant astroloy type nickel base superalloys and product formed |
US5266360A (en) * | 1991-12-20 | 1993-11-30 | United Technologies Corporation | Inhibiting coke formation by coating gas turbine elements with silica |
US5547770A (en) * | 1992-05-19 | 1996-08-20 | Sermatech International, Inc. | Multiplex aluminide-silicide coating |
US6126758A (en) * | 1992-09-05 | 2000-10-03 | Sermatech International Inc. | Aluminide-silicide coatings, coating compositions, process for coating and improved coated products |
US5649280A (en) * | 1996-01-02 | 1997-07-15 | General Electric Company | Method for controlling grain size in Ni-base superalloys |
US5897718A (en) * | 1996-04-24 | 1999-04-27 | Rolls-Royce Plc | Nickel alloy for turbine engine components |
US6537388B1 (en) * | 1996-08-23 | 2003-03-25 | Alon, Inc. | Surface alloy system conversion for high temperature applications |
US20040221927A1 (en) * | 2002-07-19 | 2004-11-11 | Raymond Edward Lee | Isothermal forging of nickel-base superalloys in air |
Also Published As
Publication number | Publication date |
---|---|
US6933012B2 (en) | 2005-08-23 |
US20040115467A1 (en) | 2004-06-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Goward et al. | Pack cementation coatings for superalloys: a review of history, theory, and practice | |
KR101523099B1 (en) | Slurry diffusion aluminide coating composition and process | |
JP3027005B2 (en) | Method for re-polishing corroded superalloy or heat-resistant steel member and re-polished member | |
US6921251B2 (en) | Aluminide or chromide coating of turbine engine rotor component | |
US6283714B1 (en) | Protection of internal and external surfaces of gas turbine airfoils | |
US7056555B2 (en) | Method for coating an internal surface of an article with an aluminum-containing coating | |
US7993759B2 (en) | Corrosion coating for turbine blade environmental protection | |
US6174448B1 (en) | Method for stripping aluminum from a diffusion coating | |
US6863927B2 (en) | Method for vapor phase aluminiding of a gas turbine blade partially masked with a masking enclosure | |
EP3094758B1 (en) | Modified slurry compositions for forming improved chromium diffusion coatings | |
JPH11172463A (en) | Aluminide diffusion coating system of superalloy | |
US6532657B1 (en) | Pre-service oxidation of gas turbine disks and seals | |
US5900102A (en) | Method for repairing a thermal barrier coating | |
EP2022868A2 (en) | Method for forming platinum aluminide diffusion coatings | |
US8124246B2 (en) | Coated components and methods of fabricating coated components and coated turbine disks | |
KR20160111410A (en) | Methods of applying chromium diffusion coatings onto selective regions of a component | |
US20060057416A1 (en) | Article having a surface protected by a silicon-containing diffusion coating | |
US6843861B2 (en) | Method for preventing the formation of secondary reaction zone in susceptible articles, and articles prepared by the method | |
US6863925B1 (en) | Method for vapor phase aluminiding including a modifying element | |
US6844086B2 (en) | Nickel-base superalloy article substrate having aluminide coating thereon, and its fabrication | |
EP3048183B1 (en) | Corrosion resistant coating application method | |
EP2020452A2 (en) | Method for forming aluminide diffusion coatings | |
EP1522607B1 (en) | Method for fabricating a coated superalloy stabilized against the formation of secondary reaction zone | |
Hall et al. | Surface treatments for nickel and nickel-base alloys |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- AFTER EXAMINER'S ANSWER OR BOARD OF APPEALS DECISION |