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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
• • 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
  • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
  • C23C14/02—Pretreatment of the material to be coated
  • C23C14/021—Cleaning or etching treatments
• • 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
  • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
  • C23C14/02—Pretreatment of the material to be coated
  • C23C14/028—Physical treatment to alter the texture of the substrate surface, e.g. grinding, polishing
• • 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
  • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
  • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
  • C23C14/14—Metallic material, boron or silicon
  • C23C14/16—Metallic material, boron or silicon on metallic substrates or on substrates of boron or silicon
• • 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
  • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
  • C23C14/58—After-treatment
  • C23C14/5873—Removal of material
• • 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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
  • C23C4/06—Metallic material
  • C23C4/073—Metallic material containing MCrAl or MCrAlY alloys, where M is nickel, cobalt or iron, with or without non-metal elements
• • 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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
  • C23C4/06—Metallic material
  • C23C4/08—Metallic material containing only metal elements
• • 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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
  • C23C4/10—Oxides, borides, carbides, nitrides or silicides; Mixtures thereof
• • 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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
  • C23C4/10—Oxides, borides, carbides, nitrides or silicides; Mixtures thereof
  • C23C4/11—Oxides
• • 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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
  • C23C4/134—Plasma spraying
• • 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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/18—After-treatment
• • 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
  • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
  • C23F1/00—Etching metallic material by chemical means
  • C23F1/10—Etching compositions
  • C23F1/14—Aqueous compositions
  • C23F1/16—Acidic compositions
  • C23F1/28—Acidic compositions for etching iron group metals
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
  • C25F3/00—Electrolytic etching or polishing
  • C25F3/02—Etching
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
  • F01D5/12—Blades
  • F01D5/28—Selecting particular materials; Particular measures relating thereto; Measures against erosion or corrosion
  • F01D5/288—Protective coatings for blades
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2230/00—Manufacture
  • F05D2230/30—Manufacture with deposition of material
  • F05D2230/31—Layer deposition
  • F05D2230/312—Layer deposition by plasma spraying
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/10—Metals, alloys or intermetallic compounds
  • F05D2300/17—Alloys
  • F05D2300/175—Superalloys
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/50—Intrinsic material properties or characteristics
  • F05D2300/516—Surface roughness
• • 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
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T50/00—Aeronautics or air transport
  • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

Definitions

• the invention relates to a turbine part, such as a turbine blade or a distributor fin for example, used in aeronautics.
• thermal barrier on the surface of a substrate or an underlayer makes it possible to protect them during use at high temperature.
• Thermal barriers are generally deposited on a first coating of the substrate, called an undercoat, which can have two roles: protecting the substrate against oxidation and promoting the adhesion of the thermal barrier.
• Such a sub-layer is generally chosen to form an alumina layer on its surface, the alumina layer fulfilling the two aforementioned roles very well, in particular when the alumina is in its coarse-grained ⁇ form.
• SPS spray deposition process by plasma suspension
• This texturing that is to say a step which seeks to obtain a particular roughness on the surface of the underlayer, is carried out by sandblasting.
• the purpose of such sandblasting is to strip the unstable oxides and the impurities, to create roughness in the underlayer, and to promote the formation of alumina.
• y-Ni/y'-Ni3AI sub-layers are currently proposed which make it possible to form a layer alumina on their surface.
• sandblasting as usually practiced strips a large part of the undercoat.
• the reduction in thickness of the undercoat is not uniform over the whole surface of the part, especially when the part has a complex geometry.
• the invention aims precisely to respond to this problem.
• the invention relates to a process for coating a substrate with a thermal barrier comprising at least the following steps:
• a step of creating a first roughness on the surface of the substrate by at least one chemical and/or electrochemical attack the first roughness being characterized by a maximum roughness value R Z 1 and an arithmetic mean of roughness along the profile Ra l;
• a step of creating a second roughness on the surface of the underlayer by at least sandblasting or electrochemical attack the second roughness being characterized by a maximum roughness value R z 2 and an arithmetic average roughness along of the profile R a 2 , the values R z 2 and R a 2 being lower than the roughness values R Z 1 and R a 1 ;
• the inventors have observed that a first high roughness makes it possible to obtain a very good lifespan of the thermal barrier.
• the first roughness is characterized by a maximum roughness value R Z 1 comprised between 13 and 16 ⁇ m and an arithmetic mean of roughness along the profile R a l comprised between 2.5 and 3.0 ⁇ m.
• roughness within the meaning of the application and unless explicitly mentioned to the contrary, is meant a pair of values comprising a maximum roughness value R z and an arithmetic mean value of roughness along the profile R a . Moreover, one roughness will be said to be “lower” than another, if the two values R z and R a of the first roughness are respectively lower than the values R z and R a of the second.
• the roughness of a surface can be measured using a roughness meter or a 3D microscope.
• the inventors have found that a method according to the invention allows excellent adhesion of the thermal barrier to the undercoat, very good resistance of the undercoat to corrosion and oxidation, and also to obtain 'a uniform y/y' sub-layer, whatever the geometry of the substrate.
• the step of creating a first roughness may include an acid etching step.
• the substrate can be exposed to an acidic solution, for example by immersion in a bath of solution.
• the acid solution may comprise fluonitric acid, nitric acid, hydrochloric acid, ferric chloride, hydrogen peroxide or a mixture of the aforementioned acids.
• the solution is chosen from a solution of fluonitric acid, a solution of hydrochloric acid and ferric chloride, a solution of nitric acid, hydrochloric acid and ferric chloride, a solution of hydrochloric acid and hydrogen peroxide or a solution of nitric acid and hydrochloric acid.
• the creation of the first roughness includes only acidic or electrochemical etching. In one embodiment of the invention, the step of creating the first roughness comprises an acid attack and an electrochemical attack.
• the substrate can be exposed to a solution comprising acetic acid, nitric acid, sulfuric acid, phosphoric acid or a mixture of these acids.
• the chemical attack or attacks can be carried out by exposure for 3 to 30 minutes to a solution of hydrochloric acid having a concentration between 30 and 50 g/L, and of ferric chloride in a concentration of 400 to 500 g/L at a temperature between 50 and 70°C.
• the electrochemical attack or attacks can be carried out by exposure for 2 to 10 minutes under a current of 3 to 20 A, and in a solution of phosphoric acid at 70% by volume, for example with 300 to 800 mL of phosphoric acid in 200 to 700 mL of water.
• the solution is chosen from a solution of nitric acid and acetic acid, a solution of sulfuric acid, or a solution of phosphoric acid.
• the creation of the first roughness includes only an electrochemical etching step.
• Creating the first roughness by exposing the substrate to a solution, whether by chemical or electrochemical attack or the joint action of the two makes it possible to create a first homogeneous roughness on the surface of the substrate. Indeed, whatever the complexity of the geometry of the substrate, such a step makes it possible to ensure that the entire surface of the substrate is exposed to equivalent conditions, thus allowing the creation of a homogeneous roughness.
• the roughness created at the surface of the substrate can be checked by macrography before the deposition of the underlayer. This step makes it possible to ensure that the texturing obtained is sufficient to guarantee good adhesion of the undercoat to the substrate.
• the substrate is chosen from single crystals of nickel, a nickel-based or cobalt-based superalloy, for example chosen from nickel-based alloys with trade names R125, R77, INCO78, DS200, CMSX4 SLS, CMSX4 PLUS or among cobalt-based alloys such as MARM509.
• the deposition of the underlayer can be carried out by spraying, by physical vapor deposition or by chemical vapor deposition, or even by HVOF spraying (for the acronym in English High Velocity Oxy Fuel) or by electrolytic deposition.
• the deposition of the underlayer is carried out by physical vapor deposition.
• Physical vapor deposition ensures the deposition of an underlayer that matches the roughness of the substrate.
• the sub-layer is preferably chosen from among a sub-layer composed of y-Ni/y′-Ni 3 Al, of NiAl, of NiAIPt, of CoCrAlY or of NiCrAlY.
• the underlayer is composed of Y-Ni/y'-Ni 3 AI.
• the underlayer is directly in contact with the substrate.
• a second roughness is created on the surface of the underlayer.
• This roughness lower than the first roughness present between the substrate and the underlayer, makes it possible to improve the resistance of the thermal barrier to the underlayer, while preserving a sufficient thickness of the underlayer, guaranteeing thus its function of resistance to oxidation and corrosion.
• the creation of the second roughness allows a fairly light stripping of the underlayer, on only a few micrometers, and thus makes it possible to maintain a good thickness of the undercoat which allows it to retain excellent resistance to oxidation and corrosion.
• the second roughness is characterized by a maximum roughness value R z 2 of between 2.5 and 3.5 ⁇ m.
• the creation of the second roughness is carried out by sandblasting.
• the creation of the second roughness can be carried out by an electrochemical etching step.
• the creation of the second roughness can be created by exposing the substrate coated with the underlayer to a solution comprising acetic acid, nitric acid, sulfuric acid, phosphoric acid or a mixture of these acids.
• the solution is chosen from a solution of nitric acid and acetic acid, a solution of sulfuric acid, and a solution of phosphoric acid.
• Another step of the method of the invention is the deposition of the thermal barrier layer by SPS.
• the deposition of the thermal barrier by SPS makes it possible to obtain a barrier of low thermal conductivity, and also makes it possible to reduce the costs of the deposition compared to other methods of the prior art.
• Figure 1 is a micrograph obtained by scanning electron microscopy of a substrate covered with an underlayer in accordance with the first steps of a method according to the invention.
• Figure 2 is a micrograph obtained by scanning electron microscopy of a substrate covered with an underlayer and a thermal barrier according to one embodiment of a method of the invention.
• FIG. 3 is a micrograph obtained by scanning electron microscopy of a substrate covered with an underlayer without a first roughness having been created between the two.
• FIG. 4 is a micrograph obtained by scanning electron microscopy of a substrate covered with an underlayer and a thermal barrier according to a method of the prior art.
• FIG. 1 is a micrograph obtained by scanning electron microscopy of a substrate 11 covered with an underlayer 12 after creation of a first roughness in accordance with the first steps of a method of the invention.
• the creation of the first roughness was achieved by exposing the substrate 11 to 3 to 30 minutes to a solution of hydrochloric acid having a concentration between 30 and 50 g / L, and ferric chloride in a concentration of 400 to 500 g/L at a temperature between 50 and 70°C.
• the roughness thus created can be characterized by its values R z and R a respectively between 13 and 16 ⁇ m and 2.5 and 3 ⁇ m for the example of embodiment shown in figure 1.
• the underlayer 12 is deposited by physical vapor deposition.
• the deposits are made by physical vapor deposition, preferably by magnetron sputtering or by evaporation.
• - a bias between -150 V and -300V. - a very low pressure in the chamber, between 0.1 and 2 Pa in the case of magnetron sputtering and between W 4 and 10' 6 Pa in the case of evaporation.
• the thickness of the underlayer 12 is uniform over the entire surface of the substrate 11.
• FIG. 2 is a micrograph obtained by scanning electron microscopy of the substrate 11 covered with an underlayer 12, illustrated in FIG. 1, on which a second roughness has been created, then a thermal barrier deposited, according to one embodiment of a method of the invention.
• the thickness of the underlayer 12 remains homogeneous over the entire surface of the substrate 11, even after the deposition of the thermal barrier 13.
• FIG. 3 is a micrograph obtained by scanning electron microscopy and represents a substrate 31 coated with an underlayer 32, without a first roughness in accordance with that of the invention having been prepared between the substrate 31 and the underlay 32.
• the underlayer was deposited by physical vapor deposition with the same parameters as above.
• the thickness of the underlayer is homogeneous over the entire surface of the substrate.
• FIG. 4 is a micrograph obtained by scanning electron microscopy and represents the substrate 31 coated with the underlayer 32, illustrated in FIG. 3, on which a thermal barrier 33 has been deposited with a process of the prior art, this is i.e. after sandblasting carried out to create a roughness on the surface of the underlayer 32 allowing the grip of the thermal barrier 33.
• FIGS. 1 to 4 illustrate that a method of the invention effectively makes it possible to obtain a thermal barrier at the surface of a substrate covered with an undercoat. layer, by ensuring good cohesion of the thermal barrier to the underlayer and by ensuring that the underlayer has a uniform thickness over the whole of the substrate, unlike a process in which only a significant roughness on the underlayer.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Plasma & Fusion (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• General Engineering & Computer Science (AREA)
• Physical Vapour Deposition (AREA)
• Coating By Spraying Or Casting (AREA)
• Laminated Bodies (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Turbine Rotor Nozzle Sealing (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=74183209

Family Applications (1)

Country Status (3)

Family Cites Families (3)

• 2020
  • 2020-08-06 FR FR2008316A patent/FR3113261B1/fr active Active
• 2021
  • 2021-08-06 WO PCT/FR2021/051449 patent/WO2022029392A1/fr active Application Filing
  • 2021-08-06 EP EP21762755.3A patent/EP4192994A1/de active Pending

Also Published As

Similar Documents

Legal Events