US20040043160A1 - Method for coating articles using a plasma transferred torchin non-transferred mode, and related methods for repairing and manufacturing articles - Google Patents
Method for coating articles using a plasma transferred torchin non-transferred mode, and related methods for repairing and manufacturing articles Download PDFInfo
- Publication number
- US20040043160A1 US20040043160A1 US10/064,893 US6489302A US2004043160A1 US 20040043160 A1 US20040043160 A1 US 20040043160A1 US 6489302 A US6489302 A US 6489302A US 2004043160 A1 US2004043160 A1 US 2004043160A1
- Authority
- US
- United States
- Prior art keywords
- substrate
- disposing
- coating
- pta
- providing
- 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
- 238000000576 coating method Methods 0.000 title claims abstract description 74
- 239000011248 coating agent Substances 0.000 title claims abstract description 60
- 238000000034 method Methods 0.000 title claims abstract description 59
- 238000004519 manufacturing process Methods 0.000 title 1
- 239000000758 substrate Substances 0.000 claims abstract description 63
- 230000008439 repair process Effects 0.000 claims abstract description 18
- 238000003466 welding Methods 0.000 claims abstract description 14
- 238000011065 in-situ storage Methods 0.000 claims abstract description 9
- 230000015556 catabolic process Effects 0.000 claims abstract description 7
- 238000006731 degradation reaction Methods 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 claims description 24
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 11
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 8
- 239000000843 powder Substances 0.000 claims description 8
- 239000012720 thermal barrier coating Substances 0.000 claims description 7
- 229910017052 cobalt Inorganic materials 0.000 claims description 6
- 239000010941 cobalt Substances 0.000 claims description 6
- 239000000919 ceramic Substances 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 229910052759 nickel Inorganic materials 0.000 claims description 5
- 229910045601 alloy Inorganic materials 0.000 claims description 4
- 239000000956 alloy Substances 0.000 claims description 4
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 229910000951 Aluminide Inorganic materials 0.000 claims description 2
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 2
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 150000001875 compounds Chemical class 0.000 claims description 2
- 239000010935 stainless steel Substances 0.000 claims description 2
- 229910001220 stainless steel Inorganic materials 0.000 claims description 2
- 229910001233 yttria-stabilized zirconia Inorganic materials 0.000 claims description 2
- 229910052727 yttrium Inorganic materials 0.000 claims description 2
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims description 2
- 229910052726 zirconium Inorganic materials 0.000 claims description 2
- 238000000151 deposition Methods 0.000 description 4
- 238000000429 assembly Methods 0.000 description 3
- 230000000712 assembly Effects 0.000 description 3
- 230000008021 deposition Effects 0.000 description 3
- 239000011324 bead Substances 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000010891 electric arc Methods 0.000 description 2
- 230000000873 masking effect Effects 0.000 description 2
- 229910000907 nickel aluminide Inorganic materials 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- 239000010963 304 stainless steel Substances 0.000 description 1
- NPXOKRUENSOPAO-UHFFFAOYSA-N Raney nickel Chemical compound [Al].[Ni] NPXOKRUENSOPAO-UHFFFAOYSA-N 0.000 description 1
- 229910000589 SAE 304 stainless steel Inorganic materials 0.000 description 1
- 229910001347 Stellite Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- AHICWQREWHDHHF-UHFFFAOYSA-N chromium;cobalt;iron;manganese;methane;molybdenum;nickel;silicon;tungsten Chemical compound C.[Si].[Cr].[Mn].[Fe].[Co].[Ni].[Mo].[W] AHICWQREWHDHHF-UHFFFAOYSA-N 0.000 description 1
- 230000002939 deleterious effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000005552 hardfacing Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- PCLURTMBFDTLSK-UHFFFAOYSA-N nickel platinum Chemical compound [Ni].[Pt] PCLURTMBFDTLSK-UHFFFAOYSA-N 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000011253 protective coating Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 229910002076 stabilized zirconia 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
- C23C24/00—Coating starting from inorganic powder
- C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
- C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
-
- 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
- C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
- C23C26/02—Coating not provided for in groups C23C2/00 - C23C24/00 applying molten material to the substrate
Definitions
- This invention relates to methods for applying coatings to articles. More particularly, this invention relates to methods for protecting articles from degradation using coatings. This invention also relates to methods for in-situ repair of an article.
- TBC systems typically comprise a metallic, oxidation-resistant layer, referred to as a “bond coat,” and a thermally resistant ceramic topcoat, often comprising stabilized zirconia.
- a metallic, oxidation-resistant layer referred to as a “bond coat”
- a thermally resistant ceramic topcoat often comprising stabilized zirconia.
- protective coatings include tungsten carbide-cobalt coatings for wear resistance, and nickel-based coatings for corrosion resistance.
- Thermal-spray coatings have been used effectively to extend the useful service lives and capabilities of articles for a considerable number of years.
- coated articles eventually require maintenance and repair.
- Repair operations often include stripping of at least some of the coating from the article, and, in some cases, a further operation, such as welding, is performed on the article in the stripped area to refurbish the underlying article.
- a further operation such as welding
- selectively applying a new coating over the stripped and refurbished area is desirable.
- current techniques for applying coatings to selective areas are often time-consuming and expensive, requiring complicated masking procedures to ensure that the new coating is sprayed in the precise area of the repair.
- One embodiment is a method for protecting an article from degradation, the method comprising providing a substrate; providing a Plasma Transferred Arc (PTA) apparatus; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the substrate using the PTA apparatus in the non-transferred arc mode.
- PTA Plasma Transferred Arc
- a second embodiment is a method for in-situ repair of a component of an assembly, the method comprising: providing a substrate, the substrate comprising a component of an assembly and coupled to the assembly; providing a PTA apparatus; welding the substrate using the PTA apparatus in a transferred arc mode to form a welded region on the substrate; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the welded region of the substrate using the PTA apparatus in the non-transferred arc mode, wherein the PTA apparatus is operated using a pilot arc power supply to dispose the at least one coating.
- FIG. 1 is a schematic representation of an exemplary PTA apparatus
- FIG. 2 is a photomicrograph of a coating deposited by the method of the present invention.
- the method of the present invention comprises providing a substrate.
- providing the substrate comprises providing a substrate comprising at least one of a metal, a ceramic, and a plastic.
- providing the substrate comprises providing a substrate comprising an alloy.
- the alloy comprises any of several metals common to industry, including at least one of nickel, cobalt, iron, aluminum, and stainless steel.
- providing the substrate comprises providing a component of a gas turbine assembly.
- Providing the component in certain embodiments, comprises removing the component from a turbine assembly.
- Such an embodiment applies, as a non-limiting example, to certain repair operations in which the component is removed from the assembly to allow access to the damaged region.
- the component alternatively may be provided as a newly manufactured component, or as a component coupled to a gas turbine assembly.
- the latter alternative, in which the component is provided coupled to an assembly is referred to herein as an “in-situ repair” method, about which more will be described herein.
- a Plasma Transferred Arc (PTA) apparatus 100 is provided.
- PTA Plasma Transferred Arc
- a large number of commercial PTA units are available, and the schematic shown in FIG. 1 is presented merely to illustrate the basic components of a typical PTA apparatus 100 .
- An electric arc is constricted by passing the arc through an orifice 102 in a nozzle 104 .
- Gas 106 passing through orifice 102 is heated to the point of ionization by the electric arc, generating a plasma 108 .
- Injected material 110 often injected into plasma 108 in powder form as shown in FIG. 1, may be used to deposit a coating on a substrate 112 , or as conventional filler material when the PTA apparatus 100 is used to weld substrate 112 .
- the non-transferred arc mode is in use when electrical current flow occurs from an electrode 114 to nozzle 104 to a first power supply 116 .
- the transferred arc mode is in use when current flow is from electrode 114 through orifice 102 to substrate 112 to a second power supply 118 .
- the non-transferred arc as used in a PTA apparatus is referred to as a “pilot arc” and is conventionally used to strike the transferred arc between nozzle 104 and substrate 112 . Additionally, the pilot arc occasionally may be used to stabilize the transferred arc during the PTA coating operation, particularly where low transferred arc power is desirable to maintain low substrate 12 temperatures.
- First power supply 116 is referred to as a “pilot arc power supply” and is generally designed to supply a significantly lower current than second power supply (“transferred arc power supply”) 118 .
- the method of the present invention further comprises setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the substrate 112 using the PTA apparatus 100 in the non-transferred arc mode, and in particular embodiments, disposing the at least one coating comprises operating the PTA apparatus 100 using a pilot arc power supply 116 to dispose the at least one coating.
- This ability enables the method of the present invention to be used, for example, in certain “in-situ repair” embodiments as described above, wherein disposing the at least one coating comprises disposing the at least one coating on the component, wherein the component is coupled to a gas turbine assembly.
- the method of the present invention provides the potential for significantly faster and more cost effective repair of components, because the conventional step of disassembling the turbine assembly is not needed.
- the PTA apparatus 100 provided for use in the method of the present invention is suitable for use in various welding operations in addition to coating methods described above.
- This welding capability can be advantageously combined with the aforementioned coating capability to provide a welding and coating operation that operates using the same equipment, thereby avoiding the need to change equipment when the processing changes from welding to coating.
- the method of the present invention further comprises welding the substrate using the PTA apparatus in a transferred arc mode to form a welded region on the substrate prior to disposing the at least one coating on the substrate using the PTA apparatus in the non-transferred arc mode.
- disposing the at least one coating comprises disposing the coating on the welded region of the substrate.
- the area of coating deposition applied by the PTA apparatus 100 operating according to the method of the present invention is sufficiently narrow to allow fine control of coating coverage such that coverage of a welded region, such as a weld bead, is advantageously accomplished without extensive use of masking, further reducing the time and cost of the overall repair.
- Injected material 110 is also referred to herein as “feedstock material,” as it serves as raw material for processing into the deposited coating.
- disposing the at least one coating comprises using a feedstock material 110 in a form selected from the group consisting of powder, wire, rod, sheet, paste, and combinations thereof.
- disposing the at least one coating comprises disposing at least one of a metal and a ceramic, for example, a bond coat material.
- a bond coat material suitable for disposition by the method of the present invention include a material comprising MCrAIX-type material, wherein M is at least one of nickel, cobalt, and iron, and wherein X is at least one of yttrium and zirconium; and a material comprising an aluminide compound, such as at least one of nickel aluminide and platinum nickel aluminide.
- disposing the at least one coating comprises disposing a thermal barrier coating, such as, for example, a material comprising yttria-stabilized zirconia.
- a thermal barrier coating such as, for example, a material comprising yttria-stabilized zirconia.
- a thermal barrier coating such as, for example, a material comprising yttria-stabilized zirconia.
- wear-resistant coatings such as tungsten carbide-cobalt material; corrosion-resistant coatings; and solders and brazes.
- further embodiments include a method for protecting an article from degradation, the method comprising providing a substrate 112 ; providing a PTA apparatus 100 ; welding the substrate 112 using the PTA apparatus 100 in a transferred arc mode to form a welded region on the substrate; setting the PTA apparatus 100 to operate in a non-transferred arc mode; and disposing at least one coating on the welded region of the substrate 112 using the PTA apparatus 100 in the non-transferred arc mode, wherein the PTA apparatus 100 is operated using a pilot arc power supply 116 to dispose the at least one coating.
- embodiments of the present invention include a method for in-situ repair of a component of an assembly, the method comprising providing a substrate, the substrate comprising a component of an assembly and coupled to the assembly; providing a PTA apparatus; welding the substrate using the PTA apparatus in a transferred arc mode to form a welded region on the substrate; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the welded region of the substrate using the PTA apparatus in the non-transferred arc mode, wherein the PTA apparatus is operated using a pilot arc power supply to dispose the at least one coating.
- a Stellite Starweld PTA hardfacing apparatus was set in non-transferred arc mode, and using the pilot arc power supply of the PTA apparatus, an MCrAIY-type coating Praxair Ni 211-2 powder was deposited on a type 304 Stainless Steel substrate using the following processing parameters:
- Powder feed rate 1-1.5 Lbs/Hr
- Powder Praxair Ni211-2 MCrAIY powder.
- the coating shown in FIG. 2, was prepared in 8 passes, had a thickness of about 0.38 mm and had a microstructure of suitable density and composition for use as a TBC bond coat.
Abstract
A method for protecting an article from degradation, and a method for in-situ repair of a component of an assembly are presented, wherein the method for protecting comprises providing a substrate; providing a Plasma Transferred Arc (PTA) apparatus; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the substrate using the PTA apparatus in the non-transferred arc mode. The method for in-situ repair comprises providing a substrate, the substrate comprising a component of an assembly and coupled to the assembly; providing a PTA apparatus; welding the substrate using the PTA apparatus in a transferred arc mode to form a welded region on the substrate; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the welded region of the substrate using the PTA apparatus in the non-transferred arc mode, wherein the PTA apparatus is operated using a pilot arc power supply to dispose the at least one coating.
Description
- This invention relates to methods for applying coatings to articles. More particularly, this invention relates to methods for protecting articles from degradation using coatings. This invention also relates to methods for in-situ repair of an article.
- Articles exposed to corrosive, abrasive, or otherwise deleterious environments are often coated with resistant materials designed to isolate the underlying material from exposure to the environment, thereby protecting the article from degradation. Many different protective systems have been developed for use in various industries and applications. Many of these coatings have been developed for use in thermal spray processes, where solid raw materials in powder, wire, or other form are injected into a flame or plasma torch, at least partially melted, and sprayed onto a substrate. For example, plasma-sprayed thermal barrier coating (TBC) systems have been developed for use in gas turbine assemblies and other high-temperature applications, to protect coated components from the effects of heat and oxidation. TBC systems typically comprise a metallic, oxidation-resistant layer, referred to as a “bond coat,” and a thermally resistant ceramic topcoat, often comprising stabilized zirconia. Other non-limiting examples of protective coatings include tungsten carbide-cobalt coatings for wear resistance, and nickel-based coatings for corrosion resistance.
- Thermal-spray coatings have been used effectively to extend the useful service lives and capabilities of articles for a considerable number of years. However, despite the effectiveness of coating technology to this end, coated articles eventually require maintenance and repair. Repair operations often include stripping of at least some of the coating from the article, and, in some cases, a further operation, such as welding, is performed on the article in the stripped area to refurbish the underlying article. In order to enhance the performance of the repaired article, selectively applying a new coating over the stripped and refurbished area is desirable. However, current techniques for applying coatings to selective areas are often time-consuming and expensive, requiring complicated masking procedures to ensure that the new coating is sprayed in the precise area of the repair. Furthermore, in complex assemblies of coated components, such as, for example, gas turbine assemblies, current techniques require removal of components from the assembly prior to the repair operation, due in part to the need to provide access to the component for welding and coating equipment. The need for removal of components increases the cost of the operation in terms of labor time and in lost revenue due to component “down-time.”
- Therefore, there is a need to provide alternative methods for depositing coatings on articles. There is a further need for methods for repairing coated articles to reduce the cost and time needed to accomplish repairs.
- Embodiments of the present invention address these and other needs. One embodiment is a method for protecting an article from degradation, the method comprising providing a substrate; providing a Plasma Transferred Arc (PTA) apparatus; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the substrate using the PTA apparatus in the non-transferred arc mode.
- A second embodiment is a method for in-situ repair of a component of an assembly, the method comprising: providing a substrate, the substrate comprising a component of an assembly and coupled to the assembly; providing a PTA apparatus; welding the substrate using the PTA apparatus in a transferred arc mode to form a welded region on the substrate; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the welded region of the substrate using the PTA apparatus in the non-transferred arc mode, wherein the PTA apparatus is operated using a pilot arc power supply to dispose the at least one coating.
- These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
- FIG. 1 is a schematic representation of an exemplary PTA apparatus; and
- FIG. 2 is a photomicrograph of a coating deposited by the method of the present invention.
- The method of the present invention comprises providing a substrate. In certain embodiments, providing the substrate comprises providing a substrate comprising at least one of a metal, a ceramic, and a plastic. In particular embodiments, providing the substrate comprises providing a substrate comprising an alloy. The alloy comprises any of several metals common to industry, including at least one of nickel, cobalt, iron, aluminum, and stainless steel.
- In some embodiments, providing the substrate comprises providing a component of a gas turbine assembly. Providing the component, in certain embodiments, comprises removing the component from a turbine assembly. Such an embodiment applies, as a non-limiting example, to certain repair operations in which the component is removed from the assembly to allow access to the damaged region. The component alternatively may be provided as a newly manufactured component, or as a component coupled to a gas turbine assembly. The latter alternative, in which the component is provided coupled to an assembly, is referred to herein as an “in-situ repair” method, about which more will be described herein.
- In the method of the present invention, a Plasma Transferred Arc (PTA)
apparatus 100 is provided. A large number of commercial PTA units are available, and the schematic shown in FIG. 1 is presented merely to illustrate the basic components of atypical PTA apparatus 100. An electric arc is constricted by passing the arc through anorifice 102 in anozzle 104.Gas 106 passing throughorifice 102 is heated to the point of ionization by the electric arc, generating aplasma 108. Injectedmaterial 110, often injected intoplasma 108 in powder form as shown in FIG. 1, may be used to deposit a coating on asubstrate 112, or as conventional filler material when thePTA apparatus 100 is used to weldsubstrate 112. There are two modes of operating a PTA apparatus. The non-transferred arc mode is in use when electrical current flow occurs from anelectrode 114 tonozzle 104 to afirst power supply 116. The transferred arc mode is in use when current flow is fromelectrode 114 throughorifice 102 tosubstrate 112 to asecond power supply 118. The non-transferred arc as used in a PTA apparatus is referred to as a “pilot arc” and is conventionally used to strike the transferred arc betweennozzle 104 andsubstrate 112. Additionally, the pilot arc occasionally may be used to stabilize the transferred arc during the PTA coating operation, particularly where low transferred arc power is desirable to maintain low substrate 12 temperatures.First power supply 116 is referred to as a “pilot arc power supply” and is generally designed to supply a significantly lower current than second power supply (“transferred arc power supply”) 118. - In conventional methods of using
commercial PTA apparatus 100, substantially all of the energy used to melt injectedmaterial 110 for the purpose ofcoating substrate 112 is provided by transferredarc power supply 118. However, in stark contrast to conventional methods, the present inventors have discovered that high-quality coatings can be applied with highly desirable control of coating placement using aconventional PTA apparatus 100 in non-transferred mode, including, for example, heating injectedmaterial 110 to deposit a coating onsubstrate 112 using energy provided substantially exclusively by the pilotarc power supply 116. Accordingly, the method of the present invention further comprises setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on thesubstrate 112 using thePTA apparatus 100 in the non-transferred arc mode, and in particular embodiments, disposing the at least one coating comprises operating thePTA apparatus 100 using a pilotarc power supply 116 to dispose the at least one coating. - The precise control of coating placement, combined with the compact configuration of the
PTA apparatus 100 relative to conventional plasma spray equipment, advantageously provides the method of the present invention with the ability to selectively apply coatings in narrow areas, such as weld beads, for example, and areas that are inaccessible to conventional coating equipment. This ability enables the method of the present invention to be used, for example, in certain “in-situ repair” embodiments as described above, wherein disposing the at least one coating comprises disposing the at least one coating on the component, wherein the component is coupled to a gas turbine assembly. By enabling in-situ repair methods, the method of the present invention provides the potential for significantly faster and more cost effective repair of components, because the conventional step of disassembling the turbine assembly is not needed. - The
PTA apparatus 100 provided for use in the method of the present invention is suitable for use in various welding operations in addition to coating methods described above. This welding capability can be advantageously combined with the aforementioned coating capability to provide a welding and coating operation that operates using the same equipment, thereby avoiding the need to change equipment when the processing changes from welding to coating. Accordingly, in certain embodiments, the method of the present invention further comprises welding the substrate using the PTA apparatus in a transferred arc mode to form a welded region on the substrate prior to disposing the at least one coating on the substrate using the PTA apparatus in the non-transferred arc mode. In particular embodiments, disposing the at least one coating comprises disposing the coating on the welded region of the substrate. The area of coating deposition applied by thePTA apparatus 100 operating according to the method of the present invention is sufficiently narrow to allow fine control of coating coverage such that coverage of a welded region, such as a weld bead, is advantageously accomplished without extensive use of masking, further reducing the time and cost of the overall repair. - Injected
material 110 is also referred to herein as “feedstock material,” as it serves as raw material for processing into the deposited coating. In certain embodiments of the present invention, disposing the at least one coating comprises using afeedstock material 110 in a form selected from the group consisting of powder, wire, rod, sheet, paste, and combinations thereof. In some embodiments, disposing the at least one coating comprises disposing at least one of a metal and a ceramic, for example, a bond coat material. Alternatives for a bond coat material suitable for disposition by the method of the present invention include a material comprising MCrAIX-type material, wherein M is at least one of nickel, cobalt, and iron, and wherein X is at least one of yttrium and zirconium; and a material comprising an aluminide compound, such as at least one of nickel aluminide and platinum nickel aluminide. - In some embodiments, disposing the at least one coating comprises disposing a thermal barrier coating, such as, for example, a material comprising yttria-stabilized zirconia. Those skilled in the art will appreciate that other types of specific useful coatings are suitable for deposition by the method of the present invention, including, but not limited to, coatings comprising at least one of wear-resistant coatings, such as tungsten carbide-cobalt material; corrosion-resistant coatings; and solders and brazes.
- In order to further capitalize on the advantages of the method of the present invention, further embodiments include a method for protecting an article from degradation, the method comprising providing a
substrate 112; providing aPTA apparatus 100; welding thesubstrate 112 using thePTA apparatus 100 in a transferred arc mode to form a welded region on the substrate; setting thePTA apparatus 100 to operate in a non-transferred arc mode; and disposing at least one coating on the welded region of thesubstrate 112 using thePTA apparatus 100 in the non-transferred arc mode, wherein thePTA apparatus 100 is operated using a pilotarc power supply 116 to dispose the at least one coating. - As described above, the fine coating deposition control and compact geometry of a
PTA apparatus 100 provides the ability in some cases to repair components without removing them from an overall assembly. Accordingly, embodiments of the present invention include a method for in-situ repair of a component of an assembly, the method comprising providing a substrate, the substrate comprising a component of an assembly and coupled to the assembly; providing a PTA apparatus; welding the substrate using the PTA apparatus in a transferred arc mode to form a welded region on the substrate; setting the PTA apparatus to operate in a non-transferred arc mode; and disposing at least one coating on the welded region of the substrate using the PTA apparatus in the non-transferred arc mode, wherein the PTA apparatus is operated using a pilot arc power supply to dispose the at least one coating. - The following example is set forth to further describe exemplary embodiments of the present invention, and should not be construed as limiting the invention in any way. A Stellite Starweld PTA hardfacing apparatus was set in non-transferred arc mode, and using the pilot arc power supply of the PTA apparatus, an MCrAIY-type coating Praxair Ni 211-2 powder was deposited on a type304 Stainless Steel substrate using the following processing parameters:
- Current: 150-200 Amps
- Voltage: 23-29 Volts
- Gun travel speed: 300-600 mm/sec
- Powder feed rate: 1-1.5 Lbs/Hr
- Powder: Praxair Ni211-2 MCrAIY powder.
- The coating, shown in FIG. 2, was prepared in8 passes, had a thickness of about 0.38 mm and had a microstructure of suitable density and composition for use as a TBC bond coat.
- While various embodiments are described herein, it will be appreciated from the specification that various combinations of elements, variations, equivalents, or improvements therein may be made by those skilled in the art, and are still within the scope of the invention as defined in the appended claims.
Claims (18)
1. A method for protecting an article from degradation, said method comprising:
providing a substrate;
providing a Plasma Transferred Arc (PTA) apparatus;
setting said PTA apparatus to operate in a non-transferred arc mode; and
disposing at least one coating on said substrate using said PTA apparatus in said non-transferred arc mode.
2. The method of claim 1 , wherein disposing said at least one coating comprises operating said PTA apparatus using a pilot arc power supply to dispose said at least one coating.
3. The method of claim 1 , further comprising welding said substrate using said PTA apparatus in a transferred arc mode to form a welded region on said substrate prior to disposing said at least one coating on said substrate using said PTA apparatus in said non-transferred arc mode.
4. The method of claim 3 , wherein disposing said at least one coating comprises disposing said coating on said welded region of said substrate.
5. The method of claim 1 , wherein providing said substrate comprises providing a substrate comprising at least one of a metal, a ceramic, and a plastic.
6. The method of claim 5 , wherein providing said substrate comprises providing a substrate comprising an alloy, said alloy comprising at least one of nickel, cobalt, iron, aluminum, and stainless steel.
7. The method of claim 1 , wherein providing said substrate comprises providing a component of a gas turbine assembly.
8. The method of claim 7 , wherein providing said component comprises removing said component from said turbine assembly.
9. The method of claim 7 , wherein disposing said at least one coating comprises disposing said at least one coating on said component wherein said component is coupled to said gas turbine assembly.
10. The method of claim 1 , wherein disposing said at least one coating comprises using a feedstock material in a form selected from the group consisting of powder, wire, rod, sheet, paste, and combinations thereof.
11. The method of claim 1 , wherein disposing said at least one coating comprises disposing at least one of a metal and a ceramic.
12. The method of claim 11 , wherein disposing said at least one coating comprises disposing a bond coat material.
13. The method of claim 12 , wherein disposing said bondcoat material comprises disposing a material comprising MCrAIX-type material, wherein M is at least one of nickel, cobalt, and iron, and wherein X is at least one of yttrium and zirconium.
14. The method of claim 12 , wherein disposing said bondcoat material comprises disposing material comprising an aluminide compound.
15. The method of claim 11 , wherein disposing said at least one coating comprises disposing a thermal barrier coating.
16. The method of claim 15 , wherein disposing said thermal barrier coating comprises disposing a material comprising yttria-stabilized zirconia.
17. A method for protecting an article from degradation, said method comprising:
providing a substrate;
providing a PTA apparatus;
welding said substrate using said PTA apparatus in a transferred arc mode to form a welded region on said substrate;
setting said PTA apparatus to operate in a non-transferred arc mode; and
disposing at least one coating on said welded region of said substrate using said PTA apparatus in said non-transferred arc mode, wherein said PTA apparatus is operated using a pilot arc power supply to dispose said at least one coating.
18. A method for in-situ repair of a component of an assembly, said method comprising:
providing a substrate, said substrate comprising a component of an assembly and coupled to said assembly;
providing a PTA apparatus;
welding said substrate using said PTA apparatus in a transferred arc mode to form a welded region on said substrate;
setting said PTA apparatus to operate in a non-transferred arc mode; and
disposing at least one coating on said welded region of said substrate using said PTA apparatus in said non-transferred arc mode, wherein said PTA apparatus is operated using a pilot arc power supply to dispose said at least one coating.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/064,893 US20040043160A1 (en) | 2002-08-27 | 2002-08-27 | Method for coating articles using a plasma transferred torchin non-transferred mode, and related methods for repairing and manufacturing articles |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/064,893 US20040043160A1 (en) | 2002-08-27 | 2002-08-27 | Method for coating articles using a plasma transferred torchin non-transferred mode, and related methods for repairing and manufacturing articles |
Publications (1)
Publication Number | Publication Date |
---|---|
US20040043160A1 true US20040043160A1 (en) | 2004-03-04 |
Family
ID=31975629
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/064,893 Abandoned US20040043160A1 (en) | 2002-08-27 | 2002-08-27 | Method for coating articles using a plasma transferred torchin non-transferred mode, and related methods for repairing and manufacturing articles |
Country Status (1)
Country | Link |
---|---|
US (1) | US20040043160A1 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080023450A1 (en) * | 2006-07-26 | 2008-01-31 | Honeywell International, Inc. | Customizable ion fusion formation system and process |
US20090208662A1 (en) * | 2004-11-04 | 2009-08-20 | United Technologies Corporation | Methods for Repairing a Workpiece |
US8563890B2 (en) | 2004-10-29 | 2013-10-22 | United Technologies Corporation | Method and apparatus for microplasma spray coating a portion of a turbine vane in a gas turbine engine |
US8822874B2 (en) | 2004-10-29 | 2014-09-02 | United Technologies Corporation | Method and apparatus for microplasma spray coating a portion of a compressor blade in a gas turbine engine |
US10494926B2 (en) | 2017-08-28 | 2019-12-03 | General Electric Company | System and method for maintaining machines |
US10717166B2 (en) | 2016-12-02 | 2020-07-21 | General Electric Company | Motorized apparatus for use with rotary machines |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4013866A (en) * | 1975-03-05 | 1977-03-22 | National Research Development Corporation | Plasma torches |
US5152058A (en) * | 1990-06-21 | 1992-10-06 | Turbine Blading Limited | Repair of turbine blades |
US5362939A (en) * | 1993-12-01 | 1994-11-08 | Fluidyne Engineering Corporation | Convertible plasma arc torch and method of use |
US6355356B1 (en) * | 1999-11-23 | 2002-03-12 | General Electric Company | Coating system for providing environmental protection to a metal substrate, and related processes |
US20030082297A1 (en) * | 2001-10-26 | 2003-05-01 | Siemens Westinghouse Power Corporation | Combustion turbine blade tip restoration by metal build-up using thermal spray techniques |
-
2002
- 2002-08-27 US US10/064,893 patent/US20040043160A1/en not_active Abandoned
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4013866A (en) * | 1975-03-05 | 1977-03-22 | National Research Development Corporation | Plasma torches |
US5152058A (en) * | 1990-06-21 | 1992-10-06 | Turbine Blading Limited | Repair of turbine blades |
US5362939A (en) * | 1993-12-01 | 1994-11-08 | Fluidyne Engineering Corporation | Convertible plasma arc torch and method of use |
US6355356B1 (en) * | 1999-11-23 | 2002-03-12 | General Electric Company | Coating system for providing environmental protection to a metal substrate, and related processes |
US20030082297A1 (en) * | 2001-10-26 | 2003-05-01 | Siemens Westinghouse Power Corporation | Combustion turbine blade tip restoration by metal build-up using thermal spray techniques |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8563890B2 (en) | 2004-10-29 | 2013-10-22 | United Technologies Corporation | Method and apparatus for microplasma spray coating a portion of a turbine vane in a gas turbine engine |
US8822874B2 (en) | 2004-10-29 | 2014-09-02 | United Technologies Corporation | Method and apparatus for microplasma spray coating a portion of a compressor blade in a gas turbine engine |
US20090208662A1 (en) * | 2004-11-04 | 2009-08-20 | United Technologies Corporation | Methods for Repairing a Workpiece |
US20080023450A1 (en) * | 2006-07-26 | 2008-01-31 | Honeywell International, Inc. | Customizable ion fusion formation system and process |
US7342195B2 (en) | 2006-07-26 | 2008-03-11 | Honeywell International, Inc. | Customizable ion fusion formation system and process |
US10717166B2 (en) | 2016-12-02 | 2020-07-21 | General Electric Company | Motorized apparatus for use with rotary machines |
US10494926B2 (en) | 2017-08-28 | 2019-12-03 | General Electric Company | System and method for maintaining machines |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
KR100671577B1 (en) | A method of providing wear-resistant coatings, and related articles | |
US20080011813A1 (en) | Repair process for coated articles | |
US6914210B2 (en) | Method of repairing a stationary shroud of a gas turbine engine using plasma transferred arc welding | |
US20100237134A1 (en) | Repair process for coated articles | |
EP1881154B1 (en) | Repair process for coated articles | |
EP1788108B1 (en) | Method for coating metals | |
US20070202269A1 (en) | Local repair process of thermal barrier coatings in turbine engine components | |
US20070087129A1 (en) | Methods for repairing a workpiece | |
US8697195B2 (en) | Method for forming a protective coating with enhanced adhesion between layers | |
EP1652953B1 (en) | Methods for repairing a workpiece | |
CN101316676A (en) | Plasma torch with corrosive protected collimator | |
US20130065077A1 (en) | Process for Applying a Heat Shielding Coating System on a Metallic Substrate | |
US20140335282A1 (en) | Method for coating a substrate | |
EP1524061B1 (en) | Process of plasma arc welding and forming low oxide coatings using a plasma arc apparatus with a environmental cell having a ring with fluid passageways | |
US20040043160A1 (en) | Method for coating articles using a plasma transferred torchin non-transferred mode, and related methods for repairing and manufacturing articles | |
Meyer et al. | Production Coating Cost Comparison | |
US8550028B2 (en) | Thermal spray stream focusing | |
US10859267B2 (en) | Oxidation resistant thermal barrier coating system for combustor panels |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: GENERAL ELECTRIC COMPANY, NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FUSARO, ROBERT ANTHONY;SOLOMON, HARVEY DONALD;REEL/FRAME:013025/0908 Effective date: 20020822 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |