EP1549782A1 - A thermal barrier coating and a method of applying such a coating - Google Patents

A thermal barrier coating and a method of applying such a coating

Info

Publication number
EP1549782A1
EP1549782A1 EP03798629A EP03798629A EP1549782A1 EP 1549782 A1 EP1549782 A1 EP 1549782A1 EP 03798629 A EP03798629 A EP 03798629A EP 03798629 A EP03798629 A EP 03798629A EP 1549782 A1 EP1549782 A1 EP 1549782A1
Authority
EP
European Patent Office
Prior art keywords
tbc
layer
substrate
thermal barrier
powder
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.)
Withdrawn
Application number
EP03798629A
Other languages
German (de)
French (fr)
Inventor
Jan Wigren
Mats-Olov Hansson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
GKN Aerospace Sweden AB
Original Assignee
Volvo Aero AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from SE0202833A external-priority patent/SE525925C2/en
Application filed by Volvo Aero AB filed Critical Volvo Aero AB
Publication of EP1549782A1 publication Critical patent/EP1549782A1/en
Withdrawn legal-status Critical Current

Links

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
    • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
    • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
    • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
    • C23C28/321—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer with at least one metal alloy 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
    • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
    • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
    • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
    • C23C28/321—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer with at least one metal alloy layer
    • C23C28/3215—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer with at least one metal alloy layer at least one MCrAlX 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
    • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
    • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
    • C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
    • C23C28/345—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one oxide 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
    • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
    • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
    • C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
    • C23C28/345—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one oxide layer
    • C23C28/3455—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one oxide layer with a refractory ceramic layer, e.g. refractory metal oxide, ZrO2, rare earth oxides or a thermal barrier system comprising at least one refractory oxide 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
    • 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
    • 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
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/007—Continuous combustion chambers using liquid or gaseous fuel constructed mainly of ceramic components
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M2900/00—Special features of, or arrangements for combustion chambers
    • F23M2900/05004—Special materials for walls or lining

Definitions

  • the present invention relates to a ceramic thermal barrier coating, TBC, deposited and attached directly to a metallic substrate itself or an intermediate bond coating deposited on such a substrate.
  • the invention also relates to a method of applying a ceramic thermal barrier coating, TBC on a substrate, the TBC being applied on the substrate or a intermediate bond coating between the substrate and the TBC, preferably by means of thermal spraying of a powder of said TBC on the substrate or bond coating.
  • the invention also relates to any metallic substrate or article coated with such a ceramic TBC.
  • the substrate or article is a constructional element operating in a high temperature environment, such as a turbine blade or combustor in a gas turbine engine.
  • TBC ceramic thermal barrier coating
  • an intermediate bond coating such as an MCrAlY-coating is applied to the metallic substrate in order to promote an efficient con- nection between the TBC and the metallic substrate.
  • the TBC is applied to the bond coating by means of any suitable deposition technique, such as thermal (preferably plasma) spraying, physical vapour deposition, PVD, or chemical vapour deposition, CVD.
  • the TBC should have a lowest possible thermal conductivity while at the same time presenting sufficient thermo-mechanical properties such as thermal shock and cycling resistance, and also be thin in order to save weight and space.
  • the method of applying, or depositing, such a coating shall be non- complicated, easily repeated, and promote efficient production of coated substrates in industrial scale (not only laboratory scale).
  • the thermal barrier coating shall be suitable as a temperature insulating material on metallic construction elements operating in harsh heat conditions, typically any such metallic construction element in gas turbine engines, such as the turbine blades or a combustor.
  • the object of the invention is achieved by means of the initially defined ceramic thermal barrier coating, characterised in that the TBC comprises at least two layers, and that a first, inner TBC layer that is directly attached to the substrate or bond coating presents a different micro structure than a second, outer TBC layer.
  • This can be achieved by means of modifying the coating deposition parameters.
  • the inven- tion suggests a preferred deposition method, which will be described later.
  • the different micro structure includes a different proportion, distribution or even orientation of pores in the first layer as compared to the second layer.
  • the first layer presents less porosity, that is a smaller proportion of pores, than the second layer.
  • the second layer has a lower thermal conductivity than the first layer, the lower thermal conductivity deriving from the difference in microstructure, while the first layer has higher strength than the second layer, the higher strength deriving from the difference in micro- structure.
  • the task of the first layer is to give the ceramic TBC a sufficient mechanical strength and adhesion to the underlying material. Due to its elevated porosity, the second layer does not by itself present a sufficient contribution to the mechanical strength of the TBC. On the other hand, thank to its increased porosity, the second layer guarantee a very low thermal conductivity.
  • the second TBC layer defines an outer layer directly exposed to the environment.
  • the first and second layers have the same chemical composition.
  • "The same in ⁇ vention" is referred to as substantially the same main components or elements, for example zirconia and dysprosia.
  • the exact proportions of the elements of the TBC layers might differ between first and second layer, but preferably also the proportions are the same for the two layers.
  • the TBC comprises stabilised zirconia, present as Zr ⁇ 2 , normally tetragonal or cubic stabilised zirconia.
  • the stabilisation of the zirconia can be obtained by means of any stabiliser well known within the state of art, such as any metallic oxide selected from the group consisting of erbia, neodymia, gadolinia, yttria , calcia , magnesia, india , scandia and ytterbia, and mixtures thereof.
  • any stabiliser well known within the state of art such as any metallic oxide selected from the group consisting of erbia, neodymia, gadolinia, yttria , calcia , magnesia, india , scandia and ytterbia, and mixtures thereof.
  • the TBC composition might also comprise any metal oxide containing any quadrivalent metallic ion selected from the group consisting of hafnium dioxide, cerium dioxide, uranium dioxide, and mixtures thereof.
  • the TBC composition might also comprise any metal oxide selected from the group consisting of nickel oxide, cobalt oxide, or chromium oxide.
  • the zirconia is stabilised by means of dysprosia, Dy ⁇ 2.
  • Dy ⁇ 2 the proportion of dysprosia is between 2 and 30 wt%, preferably between 10 and 20 wt%.
  • the thickness of the second layer should be larger than that of the first layer.
  • the thickness of the first layer should be 10-100 micrometers, preferably 40-75 micrometers.
  • the invention also relates to a coated metallic substrate, characterised in that it comprises a ceramic thermal barrier coating according to the invention.
  • a bond coating might be sandwiched between the metallic substrate and the TBC.
  • Such a bond coating may comprise a metal oxide, preferably alumina, layer on the metallic substrate.
  • the bond coating may also comprise an aluminide, a platinum aluminide, an MCrAlY alloy or other aluminium-containing alloy coating on the metallic substrate, and possibly a metallic oxide, preferably alumina, layer deposited thereon.
  • the metallic substrate is a nickel superalloy or a cobalt superalloy.
  • the object of the invention is also achieved by means of the initially defined method, characterised in that at least two layers of ceramic TBC are applied to the substrate or bond coating, and that the powder particles used for applying a first TBC layer adjacent to the substrate or bond coating present a different microstructure than the powder particles used for subsequently applying a second TBC layer onto the coated substrate.
  • the powder particles used for applying the first TBC layer present a lower porosity than the powder particles used for subsequently applying the second TBC layer onto the coated substrate.
  • the powder particles to be used for the application of the first TBC layer present a dense sintered structure.
  • the inventive method preferably comprises the step of sintering agglom- erates of powder grains in order to form said powder particles.
  • the powder particles to be used for the application of the second TBC layer present a porous structure. It has proven advantageous if each powder particle comprises an agglomerate of powder grains surrounded by a shell or coating of melted powder material. Such a microstructure might be achieved by including in the method the step of HO SP- treatment of agglomerates of powder grains in order to form said powder particles.
  • the agglomerates of powder grains that are either sintered or HOSPED are normally produced through a process in which a batch of powder, with a grain size of for example 0,5-5 micrometers, preferably 1-2 micrometers, is introduced in a liquid mixture that contains a binder, and then let to dry under such conditions that agglomerates with a typical diameter of 10-150 micrometers are formed as the liquid is eliminated.
  • Fig. 1 is a schematic section, to an enlarged scale, of a mechanical superalloy article comprising a ceramic heat barrier coating formed in accordance with the invention
  • Fig. 2 is a schematic section of a device for deposition of a coating according to the invention and operating in accordance with the in- • ventive method.
  • the mechanical article shown in fig. 1 comprises a ceramic heat barrier coating (TBC) 1 that is deposited in accordance with the inventive method on a metallic substrate 2 made of a superalloy.
  • TBC ceramic heat barrier coating
  • the substrate. 2 is also covered by an intermediate metallic underlayer or bond coating 3, deposited on the substrate 2 by any process known in the art (PVD, CVD, thermal spraying, etc.).
  • the ceramic TBC consists of a zirconia base and a dysprosium oxide for stabilising the zirconia and reducing the thermal conductivity of the ceramic.
  • the ceramic may also contain an additional metal oxide comprising a quadrivalent metallic ion having an atomic mass greater than the atomic mass of zirconium ions.
  • the quadrivalent metallic ion may be cerium, hafnium, or uranium.
  • the ceramic TBC is subdivided into two individual layers of substan- tially the same chemical composition.
  • a first layer 4 attached to the bond coating 3, and a second, outer layer 5 attached to the first layer.
  • the first layer is relatively dense, thereby adhering well to the bond coating and presenting a higher mechanical strength than the second layer 5.
  • the second layer 5 presents a more open, porous structure than the first layer 4. Due to its porous structure the second layer has an even further decreased thermal conductivity than would otherwise be the case. However, the price of the improved conductivity properties is a reduced thermal shock or cycling resistance which is remarkably lower than that of the first layer 4. As a result of their different microstructure, the first and second layers supplement each other with their individual contribution to mechanical strength and low thermal conductivity respectively.
  • a first powder is formed by the ceramic that forms the first layer 4 and a second powder is formed by the ceramic that forms the second layer 5.
  • the ceramic TBC has been deposited by means of plasma spraying.
  • a plasma spraying device 6 is schematically shown in fig. 2.
  • the device 6 comprises an anode 7 surrounding a cathode 8 and forming a nozzle for gases, this kind of device being well known in the state of art and needing no further detailed explanation.
  • An electric arc and a plasma jet 9 is generated by means of the anode 7, cathode 8 and gases flowing through the nozzle.
  • the device further comprises a means 10 for introducing a stream of powder particles 12 into the plasma jet 9.
  • the jet 9 is directed towards a substrate 13 and will transport the powder particles 12 towards the substrate 13 while at the same time at least partly melting said particles 12.
  • the first TBC layer 4 is formed on the substrate 2, or more precisely on a bond coating 3 covering the substrate 2, by introducing relatively dense, pre-sintered powder parti- clesl2 into the jet 9.
  • the powder particles 12 used for producing the first layer 4 have been formed by means of a process as described earlier in this text, that is through an agglomeration and sintering procedure.
  • the particles 12, or at least a substantial or, preferably, major part thereof, for producing the first layer 4 are fully or nearly fully melted as they hit the substrate 2/bond coating 3, and will form a dense, porous-free layer 4. Dense is referred to as less than 5% porosity by optical microscopy at less than 200X.
  • a second layer 5 is formed by subsequently to the introduction of the first powder introducing powder particles 12 with a different microstructure than before.
  • the powder particles for producing the second layer have a more open, porous structure than the first powder particles.
  • they have been produced in the way described earlier in the text, that is by an agglomeration/HOSP process, wherein HOSP process is referred to as Homogeneous Oven Spherical Powder process, which is a well known process in the state of art.
  • the powder particles 12 for producing the second layer 5 will be only partly melted as they hit the first layer 4 or any underlying material whatever it would be.
  • a previously formed shell or coating surrounding the agglomerated powder particle is melted by the jet 9.
  • the porosity is mainly laminar, the pores thereby being flattened out in a plane generally parallel to the plane of the underlying material 2, 3, 4.
  • the porosity is above 5% as a contrast to the first layer with its porosity of less than 5%.
  • Such parameters include current (voltage), gas flow, powder feed rate, powder temperature, powder velocity, powder size, powder introduction site (in relation to jet and distance to substrate), substrate temperature.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Combustion & Propulsion (AREA)
  • Coating By Spraying Or Casting (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)

Abstract

A ceramic thermal barrier coating, TBC, deposited and attached directly to a metallic substrate (2) itself or an intermediate bond coating (3) deposited on such a substrate (2). The TBC comprises at least two layers, wherein a first, inner TBC layer that is directly attached to the substrate (2) or bond coating (3) presents a different microstructure than a second, outer TBC layer.

Description

A thermal barrier coating and a method of applying such a coating
TECHNICAL FIELD
The present invention relates to a ceramic thermal barrier coating, TBC, deposited and attached directly to a metallic substrate itself or an intermediate bond coating deposited on such a substrate.
The invention also relates to a method of applying a ceramic thermal barrier coating, TBC on a substrate, the TBC being applied on the substrate or a intermediate bond coating between the substrate and the TBC, preferably by means of thermal spraying of a powder of said TBC on the substrate or bond coating.
The invention also relates to any metallic substrate or article coated with such a ceramic TBC. In particular, the substrate or article is a constructional element operating in a high temperature environment, such as a turbine blade or combustor in a gas turbine engine.
BACKGROUND OF THE INVENTION
The demand for increased operating temperature in gas turbine engines has led to the development of ceramic thermal barrier coating (TBC) materials that are deposited onto metallic parts such as turbine blades that are highly exposed to such high temperatures. The task of the TBC materials is to thermally insulate the metallic parts in order to prolong their service life and prevent them from rapid degeneration due to the severe operative conditions.
Normally an intermediate bond coating such as an MCrAlY-coating is applied to the metallic substrate in order to promote an efficient con- nection between the TBC and the metallic substrate. Subsequently the TBC is applied to the bond coating by means of any suitable deposition technique, such as thermal (preferably plasma) spraying, physical vapour deposition, PVD, or chemical vapour deposition, CVD.
The TBC should have a lowest possible thermal conductivity while at the same time presenting sufficient thermo-mechanical properties such as thermal shock and cycling resistance, and also be thin in order to save weight and space.
THE OBJECT OF THE INVENTION
It is an object of the invention to present a ceramic thermal barrier coating and a method of applying such a coating that results in a coating that combines the properties of low thermal conductivity, sufficient mechanical strength and low weight.
The method of applying, or depositing, such a coating shall be non- complicated, easily repeated, and promote efficient production of coated substrates in industrial scale (not only laboratory scale).
The thermal barrier coating shall be suitable as a temperature insulating material on metallic construction elements operating in harsh heat conditions, typically any such metallic construction element in gas turbine engines, such as the turbine blades or a combustor.
BRIEF DESCRIPTION OF THE INVENTION
The object of the invention is achieved by means of the initially defined ceramic thermal barrier coating, characterised in that the TBC comprises at least two layers, and that a first, inner TBC layer that is directly attached to the substrate or bond coating presents a different micro structure than a second, outer TBC layer. This can be achieved by means of modifying the coating deposition parameters. The inven- tion suggests a preferred deposition method, which will be described later.
According to a preferred embodiment the different micro structure includes a different proportion, distribution or even orientation of pores in the first layer as compared to the second layer. Most preferably, the first layer presents less porosity, that is a smaller proportion of pores, than the second layer.
The second layer has a lower thermal conductivity than the first layer, the lower thermal conductivity deriving from the difference in microstructure, while the first layer has higher strength than the second layer, the higher strength deriving from the difference in micro- structure. The task of the first layer is to give the ceramic TBC a sufficient mechanical strength and adhesion to the underlying material. Due to its elevated porosity, the second layer does not by itself present a sufficient contribution to the mechanical strength of the TBC. On the other hand, thank to its increased porosity, the second layer guarantee a very low thermal conductivity. Preferably, the second TBC layer defines an outer layer directly exposed to the environment.
According to a preferred embodiment of the invention, the first and second layers have the same chemical composition. "The same in^ vention" is referred to as substantially the same main components or elements, for example zirconia and dysprosia. The exact proportions of the elements of the TBC layers might differ between first and second layer, but preferably also the proportions are the same for the two layers. Preferably, the TBC comprises stabilised zirconia, present as Zrθ2, normally tetragonal or cubic stabilised zirconia. The stabilisation of the zirconia can be obtained by means of any stabiliser well known within the state of art, such as any metallic oxide selected from the group consisting of erbia, neodymia, gadolinia, yttria , calcia , magnesia, india , scandia and ytterbia, and mixtures thereof.
The TBC composition might also comprise any metal oxide containing any quadrivalent metallic ion selected from the group consisting of hafnium dioxide, cerium dioxide, uranium dioxide, and mixtures thereof.
The TBC composition might also comprise any metal oxide selected from the group consisting of nickel oxide, cobalt oxide, or chromium oxide.
Preferably, however, the zirconia is stabilised by means of dysprosia, Dyθ2. Typically, the proportion of dysprosia is between 2 and 30 wt%, preferably between 10 and 20 wt%.
The thickness of the second layer should be larger than that of the first layer. The thickness of the first layer should be 10-100 micrometers, preferably 40-75 micrometers.
The invention also relates to a coated metallic substrate, characterised in that it comprises a ceramic thermal barrier coating according to the invention.
It should be understood that a bond coating might be sandwiched between the metallic substrate and the TBC. Such a bond coating may comprise a metal oxide, preferably alumina, layer on the metallic substrate. The bond coating may also comprise an aluminide, a platinum aluminide, an MCrAlY alloy or other aluminium-containing alloy coating on the metallic substrate, and possibly a metallic oxide, preferably alumina, layer deposited thereon.
Typically, the metallic substrate is a nickel superalloy or a cobalt superalloy.
The object of the invention is also achieved by means of the initially defined method, characterised in that at least two layers of ceramic TBC are applied to the substrate or bond coating, and that the powder particles used for applying a first TBC layer adjacent to the substrate or bond coating present a different microstructure than the powder particles used for subsequently applying a second TBC layer onto the coated substrate.
Preferably, the powder particles used for applying the first TBC layer present a lower porosity than the powder particles used for subsequently applying the second TBC layer onto the coated substrate.
According to a preferred embodiment of the invention, the powder particles to be used for the application of the first TBC layer present a dense sintered structure. In order to achieve such a structure, the inventive method preferably comprises the step of sintering agglom- erates of powder grains in order to form said powder particles.
Preferably, the powder particles to be used for the application of the second TBC layer present a porous structure. It has proven advantageous if each powder particle comprises an agglomerate of powder grains surrounded by a shell or coating of melted powder material. Such a microstructure might be achieved by including in the method the step of HO SP- treatment of agglomerates of powder grains in order to form said powder particles.
The agglomerates of powder grains that are either sintered or HOSPED are normally produced through a process in which a batch of powder, with a grain size of for example 0,5-5 micrometers, preferably 1-2 micrometers, is introduced in a liquid mixture that contains a binder, and then let to dry under such conditions that agglomerates with a typical diameter of 10-150 micrometers are formed as the liquid is eliminated.
Further features and advantages of the present invention will be described in the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further described with reference to the drawings, on which:
Fig. 1 is a schematic section, to an enlarged scale, of a mechanical superalloy article comprising a ceramic heat barrier coating formed in accordance with the invention, and
Fig. 2 is a schematic section of a device for deposition of a coating according to the invention and operating in accordance with the in- • ventive method.
DETAILED DESCRIPTION OF THE INVENTION
The mechanical article shown in fig. 1 comprises a ceramic heat barrier coating (TBC) 1 that is deposited in accordance with the inventive method on a metallic substrate 2 made of a superalloy. The substrate. 2 is also covered by an intermediate metallic underlayer or bond coating 3, deposited on the substrate 2 by any process known in the art (PVD, CVD, thermal spraying, etc.).
The bond coating 3 may be an oxide-corrosion-resistant alumino- forming alloy of the MCrAlY type (M=Ni and/ or Co and/ or Fe) or a nickel or cobalt aluminide, possibly modified by the addition of chromium and/ or one or more precious metals selected from platinum, palladium, ruthenium, iridium, osmium and rhodium.
The ceramic TBC consists of a zirconia base and a dysprosium oxide for stabilising the zirconia and reducing the thermal conductivity of the ceramic. To decrease thermal conductivity further, the ceramic may also contain an additional metal oxide comprising a quadrivalent metallic ion having an atomic mass greater than the atomic mass of zirconium ions. The quadrivalent metallic ion may be cerium, hafnium, or uranium.
The ceramic TBC is subdivided into two individual layers of substan- tially the same chemical composition. A first layer 4 attached to the bond coating 3, and a second, outer layer 5 attached to the first layer. The first layer is relatively dense, thereby adhering well to the bond coating and presenting a higher mechanical strength than the second layer 5.
The second layer 5 presents a more open, porous structure than the first layer 4. Due to its porous structure the second layer has an even further decreased thermal conductivity than would otherwise be the case. However, the price of the improved conductivity properties is a reduced thermal shock or cycling resistance which is remarkably lower than that of the first layer 4. As a result of their different microstructure, the first and second layers supplement each other with their individual contribution to mechanical strength and low thermal conductivity respectively.
In other words, a first powder is formed by the ceramic that forms the first layer 4 and a second powder is formed by the ceramic that forms the second layer 5.
The ceramic TBC has been deposited by means of plasma spraying. A plasma spraying device 6 is schematically shown in fig. 2. The device 6 comprises an anode 7 surrounding a cathode 8 and forming a nozzle for gases, this kind of device being well known in the state of art and needing no further detailed explanation. An electric arc and a plasma jet 9 is generated by means of the anode 7, cathode 8 and gases flowing through the nozzle. The device further comprises a means 10 for introducing a stream of powder particles 12 into the plasma jet 9. The jet 9 is directed towards a substrate 13 and will transport the powder particles 12 towards the substrate 13 while at the same time at least partly melting said particles 12.
According to the invention, the first TBC layer 4 is formed on the substrate 2, or more precisely on a bond coating 3 covering the substrate 2, by introducing relatively dense, pre-sintered powder parti- clesl2 into the jet 9. The powder particles 12 used for producing the first layer 4 have been formed by means of a process as described earlier in this text, that is through an agglomeration and sintering procedure.
The particles 12, or at least a substantial or, preferably, major part thereof, for producing the first layer 4 are fully or nearly fully melted as they hit the substrate 2/bond coating 3, and will form a dense, porous-free layer 4. Dense is referred to as less than 5% porosity by optical microscopy at less than 200X.
Then a second layer 5 is formed by subsequently to the introduction of the first powder introducing powder particles 12 with a different microstructure than before. The powder particles for producing the second layer have a more open, porous structure than the first powder particles. Preferably, they have been produced in the way described earlier in the text, that is by an agglomeration/HOSP process, wherein HOSP process is referred to as Homogeneous Oven Spherical Powder process, which is a well known process in the state of art.
The powder particles 12 for producing the second layer 5 will be only partly melted as they hit the first layer 4 or any underlying material whatever it would be. Preferably, mainly, or only, a previously formed shell or coating surrounding the agglomerated powder particle is melted by the jet 9. As a result a porous second layer 5 is formed. The porosity is mainly laminar, the pores thereby being flattened out in a plane generally parallel to the plane of the underlying material 2, 3, 4. The porosity is above 5% as a contrast to the first layer with its porosity of less than 5%.
In order to perform the steps mentioned above, different spray parameters need to be correctly adjusted. Such parameters include current (voltage), gas flow, powder feed rate, powder temperature, powder velocity, powder size, powder introduction site (in relation to jet and distance to substrate), substrate temperature.
The above parameters will affect coating properties such as micro- structure, hardness, strength, stresses, etc, which will in their turn affect the performance and service life of the ceramic TBC and the coated metallic substrate or article 2. It should be realised that the above presentation of the invention has been made by way of example, and that alternative embodiments will be obvious for a man skilled in the art. However, the scope of protec- tion claimed is defined in the patent claims supported by the description and the annexed drawings.

Claims

PATENT CLAIMS
1. A ceramic thermal barrier coating, TBC, deposited and attached directly to a metallic substrate (2) itself or an intermediate bond coating (3) deposited on such a substrate (2), characterised in that the TBC (1) comprises at least two layers (4,5), and that a first, inner TBC layer (4) that is directly attached to the substrate (2) or bond coating (3) presents a different microstructure than a second, outer TBC layer (5).
2. A ceramic thermal barrier coating according to claim 1, characterised in that the first layer (4) presents a lower porosity than the second layer(5).
3. A ceramic thermal barrier coating according to claim 1 or 2, characterised in that the second layer (5) has a lower thermal conductivity than the first layer (4), the lower thermal conductivity deriving from the difference in microstructure.
4. A ceramic thermal barrier according to any one of claims 1 or 2, characterised in that the first layer (4) has higher strength than the second layer (5), the higher strength deriving from the difference in microstructure .
5. A ceramic thermal barrier coating according to any one of claims 1- 4, characterised in that the second TBC layer (5) defines an outer layer directly exposed to the environment.
6. A ceramic thermal barrier coating according to any one of claims 1- 5, characterised in that the first and second layers (4,5) have the same chemical composition.
7. A ceramic thermal barrier coating according to any one of claims 1- 6, characterised in that it comprises stabilised zirconia, preferably dysprosia-stabilised zirconia.
8. A ceramic thermal barrier coating according any one of claims 1-7, characterised in that it has been applied by means of thermal spraying, preferably by means of plasma spraying.
9. A coated metallic substrate (2), characterised in that it comprises a ceramic thermal barrier coating (1) according to any one of claims
1-8.
10. A coated metallic substrate (2) according to claim 9, characterised in that it comprises a bond coating (3) sandwiched between the substrate (2) and the ceramic thermal barrier coating (1).
11. A method of applying a ceramic thermal barrier coating (1), TBC on a substrate (2), the TBC being applied on the substrate (2) or an intermediate bond coating (3) between the substrate (2) and the TBC, characterised in that at least two layers (4,5) of ceramic TBC are applied to the substrate (2) or bond coating (3), and that the powder particles used for applying a first TBC layer (4) adjacent to the substrate (2) or bond coating (3) present a different microstructure than the powder particles used for subsequently applying a second TBC layer (5) onto the coated substrate (2).
12. A method according to claim 11, characterised in that the powder particles used for applying the first TBC layer (4) present a lower porosity than the powder particles used for subsequently applying the second TBC layer (5) onto the coated substrate (2).
13. A method according to claim 11 or 12, characterised in that the powder particles to be used for the application of the first TBC layer (4) present a dense sintered structure.
14. A method according to claim 13, characterised in that it comprises the step of sintering agglomerates of powder grains to said powder particles.
15. A method according to any one of claims 11-14, characterised in that the powder particles to be used for the application of the second
TBC layer (5) present a porous structure.
16. A method according to claim 15, characterised in that each powder particle comprises an agglomerate of powder grains sur- rounded by a shell of melted powder material.
17. A method according to claim 15 or 16, characterised in that it comprises the step of HOSP-treatment of agglomerates of powder grains in order to form said powder particles.
18. A method according to any one of claims 11-17, characterised in that the first and second ceramic TBC layer (4,5) has the same chemical composition.
19. A method according to any one of claims 11-18, characterised in that the TBC comprises stabilised zirconia, preferably dysprosia- stabilised zirconia.
20. A method according to claim any one of claims 11-19, character- ised in that the diameter of the powder particles is 10-150 micrometers.
21. A method according to any one of claims 11-20, characterised in that the diameter of the powder grains forming said powder particles is 0,5-5 micrometers, preferably 1-2 micrometers.
22. A method according to any one of claims 11-21, characterised in that the TBC is applied by means of thermal spraying of a powder of said TBC on the substrate (2) or bond coating (3).
23. A method according to any one of claims 11-22, characterised in that the TBC is applied by means of plasma spraying.
EP03798629A 2002-09-25 2003-09-17 A thermal barrier coating and a method of applying such a coating Withdrawn EP1549782A1 (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US31957302P 2002-09-25 2002-09-25
SE0202833A SE525925C2 (en) 2002-09-25 2002-09-25 Ceramic thermal barrier coating for blades of gas turbine engine, has inner thermal barrier coating layer with different microstructure than outer thermal barrier coating layer
SE0202833 2002-09-25
US319573P 2002-09-25
PCT/SE2003/001472 WO2004029330A1 (en) 2002-09-25 2003-09-17 A thermal barrier coating and a method of applying such a coating

Publications (1)

Publication Number Publication Date
EP1549782A1 true EP1549782A1 (en) 2005-07-06

Family

ID=32044761

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03798629A Withdrawn EP1549782A1 (en) 2002-09-25 2003-09-17 A thermal barrier coating and a method of applying such a coating

Country Status (5)

Country Link
EP (1) EP1549782A1 (en)
JP (1) JP4616648B2 (en)
AU (1) AU2003265038A1 (en)
RU (1) RU2325467C2 (en)
WO (1) WO2004029330A1 (en)

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7326470B2 (en) 2004-04-28 2008-02-05 United Technologies Corporation Thin 7YSZ, interfacial layer as cyclic durability (spallation) life enhancement for low conductivity TBCs
US7799716B2 (en) * 2006-03-03 2010-09-21 Sulzer Metco (Us), Inc. Partially-alloyed zirconia powder
WO2007112783A1 (en) * 2006-04-06 2007-10-11 Siemens Aktiengesellschaft Layered thermal barrier coating with a high porosity, and a component
US8372488B2 (en) * 2006-05-01 2013-02-12 General Electric Company Methods and apparatus for thermal barrier coatings with improved overall thermal insulation characteristics
CA2585992C (en) * 2006-06-08 2014-06-17 Sulzer Metco (Us) Inc. Dysprosia stabilized zirconia abradable
DE102008007870A1 (en) 2008-02-06 2009-08-13 Forschungszentrum Jülich GmbH Thermal barrier coating system and process for its preparation
US20110033284A1 (en) * 2009-08-04 2011-02-10 United Technologies Corporation Structurally diverse thermal barrier coatings
RU2445199C2 (en) * 2010-03-25 2012-03-20 Общество с ограниченной ответственностью "Производственное предприятие Турбинаспецсервис" Method of hardening turbo machine nozzle vane unit made from nickel and cobalt alloys
RU2479669C2 (en) * 2010-09-13 2013-04-20 Научно-производственное некоммерческое партнерство "ТЕХНОПАРК АВИАЦИОННЫХ ТЕХНОЛОГИЙ" Thermal protective coating obtaining method
FR2972449B1 (en) * 2011-03-07 2013-03-29 Snecma METHOD FOR PRODUCING A THERMAL BARRIER IN A MULTILAYER SYSTEM FOR PROTECTING A METAL PIECE AND PIECE EQUIPPED WITH SUCH A PROTECTION SYSTEM
RU2496911C2 (en) * 2011-12-13 2013-10-27 Общество с ограниченной ответственностью "Научно-производственное предприятие "Уралавиаспецтехнология" Method of applying heat coating of nickel or cobalt alloy on gas turbine parts
RU2479666C1 (en) * 2011-12-22 2013-04-20 Общество с ограниченной ответственностью "Научно-производственное предприятие "Уралавиаспецтехнология" Formation method of thermal protective coating on parts of gas turbines from nickel and cobalt alloys
DE102012200560B4 (en) * 2012-01-16 2014-08-21 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. A method of producing a ceramic layer on a surface formed of a Ni-based alloy and a ceramic layer article
US9144841B1 (en) * 2012-11-15 2015-09-29 The Boeing Company In-mold metallization of composite structures
EP2971686B1 (en) * 2013-03-15 2018-10-17 United Technologies Corporation Coated articles and manufacture methods
DE102014222686A1 (en) * 2014-11-06 2016-05-12 Siemens Aktiengesellschaft Double-layered thermal barrier coating by different coating methods
RU2600636C2 (en) * 2015-03-04 2016-10-27 Российская Федерация, от имени которой выступает Государственная корпорация по атомной энергии "Росатом" Method of producing nanocrystalline powder of zirconium dioxide
RU2613005C1 (en) * 2015-12-03 2017-03-14 Общество С Ограниченной Ответственностью "Твинн" Thermal insulation coating ceramic layer material
JP7228357B2 (en) * 2018-10-04 2023-02-24 株式会社フルヤ金属 Volatilization suppression part and its manufacturing method
RU2697758C1 (en) * 2019-01-14 2019-08-19 федеральное государственное бюджетное образовательное учреждение высшего образования "Уфимский государственный авиационный технический университет" Method of applying heat-resistant coatings y-mo-o from vacuum-arc discharge plasma
CN113930710B (en) * 2021-10-14 2023-09-26 广东省科学院新材料研究所 Thermal barrier coating material, preparation method and application thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2059806A (en) * 1979-09-06 1981-04-29 Gen Motors Corp Abradable ceramic seal and method of making same
EP0086938A2 (en) * 1982-02-16 1983-08-31 The Perkin-Elmer Corporation Hollow sphere ceramic particles for abradable coatings
US20040197580A1 (en) * 2000-12-08 2004-10-07 Dorfman Mitchell R. Method of producinhg a pre-alloyed stabilized zironia powder

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4503130A (en) * 1981-12-14 1985-03-05 United Technologies Corporation Prestressed ceramic coatings
US4576874A (en) * 1984-10-03 1986-03-18 Westinghouse Electric Corp. Spalling and corrosion resistant ceramic coating for land and marine combustion turbines
JPH0657396A (en) * 1992-08-07 1994-03-01 Mazda Motor Corp Formation of heat insulating thermally sprayed layer
CA2110007A1 (en) * 1992-12-29 1994-06-30 Adrian M. Beltran Thermal barrier coating process
JPH0967662A (en) * 1995-08-30 1997-03-11 Toshiba Corp Ceramic-coated member
JPH1161438A (en) * 1997-08-27 1999-03-05 Toshiba Corp Heat shielding coating member and its production
US5876860A (en) * 1997-12-09 1999-03-02 N.V. Interturbine Thermal barrier coating ceramic structure
JP3371083B2 (en) * 1998-01-21 2003-01-27 明和ゴム工業株式会社 Ceramic roll for corona discharge treatment and method for producing the same
FR2798654B1 (en) * 1999-09-16 2001-10-19 Snecma LOW THERMAL CONDUCTIVITY THERMAL BARRIER COMPOSITION, SUPERALLOY MECHANICAL PART PROTECTED BY A CERAMIC COATING HAVING SUCH A COMPOSITION, AND METHOD FOR PRODUCING THE CERAMIC COATING
JP2001342553A (en) * 2000-06-02 2001-12-14 Osaka Gas Co Ltd Method for forming alloy protection coating
JP3872632B2 (en) * 2000-06-09 2007-01-24 三菱重工業株式会社 Thermal barrier coating material, gas turbine member and gas turbine using the same
JP3631982B2 (en) * 2000-06-16 2005-03-23 三菱重工業株式会社 Manufacturing method of thermal barrier coating material

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2059806A (en) * 1979-09-06 1981-04-29 Gen Motors Corp Abradable ceramic seal and method of making same
EP0086938A2 (en) * 1982-02-16 1983-08-31 The Perkin-Elmer Corporation Hollow sphere ceramic particles for abradable coatings
US20040197580A1 (en) * 2000-12-08 2004-10-07 Dorfman Mitchell R. Method of producinhg a pre-alloyed stabilized zironia powder

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of WO2004029330A1 *

Also Published As

Publication number Publication date
RU2325467C2 (en) 2008-05-27
AU2003265038A1 (en) 2004-04-19
JP2006501363A (en) 2006-01-12
JP4616648B2 (en) 2011-01-19
RU2005112706A (en) 2006-05-27
WO2004029330A1 (en) 2004-04-08

Similar Documents

Publication Publication Date Title
WO2004029330A1 (en) A thermal barrier coating and a method of applying such a coating
US7258934B2 (en) Thermal barrier coating and a method of applying such a coating
US9085490B2 (en) High purity zirconia-based thermally sprayed coatings and processes for the preparation thereof
US8603930B2 (en) High-purity fused and crushed zirconia alloy powder and method of producing same
EP1829984B1 (en) Process for making a high density thermal barrier coating
US20160333455A1 (en) Thermal Barrier Coating with Lower Thermal Conductivity
JP2010209472A (en) Target for vaporizing under electron beam, method for manufacturing the same, thermal barrier material and coating obtained from the target, and mechanical parts including the coating
WO2011019486A1 (en) Thermal barrier coating systems
EP2767525B1 (en) Ceramic powders and methods therefor
US7041383B2 (en) Durable thermal barrier coating having low thermal conductivity
US20080044663A1 (en) Dual layer ceramic coating
EP2778250A2 (en) Coating systems and methods therefor
EP1927671B1 (en) Improved plasma-spray powder manufacture technique
JP2003041358A (en) Process for applying heat shielding coating system on metallic substrate
Najafizadeh et al. Thermal barrier ceramic coatings
CN101365815A (en) Alloy composite for protective coating preparation, application thereof, high-temperature alloy product applying the method and coated with the composite
Cui et al. Thermal durability of thermal barrier coatings with bond coat composition in cyclic thermal exposure
CA2549091C (en) Durable thermal barrier coating having low thermal conductivity
US20100028549A1 (en) Dispersion Strengthened Rare Earth Stabilized Zirconia
NL2018995B1 (en) Self-healing particles for high temperature ceramics
US20090258214A1 (en) Vapor-deposited coating and thermally stressable component having such a coating, and also a process and apparatus for producing such a coating
SE525925C2 (en) Ceramic thermal barrier coating for blades of gas turbine engine, has inner thermal barrier coating layer with different microstructure than outer thermal barrier coating layer
Il'yushchenko et al. Optimisation of the technology of production of multilayered thermal barrier coatings
Agarwal et al. Influence of the interface healing between the splashed particles and underlying bond coating on the cyclic oxidation behavior of LPPS MCrAlY bond coats

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20050425

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20080110

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: GKN AEROSPACE SWEDEN AB

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20140401