Component with multi-ply thermal insulation layer and modified connecting layer, and method

Abstract

The invention relates to a component (1) having a two-ply thermal insulation layer (4) at least comprising a substrate (4), in particular a metal substrate, an adhesion promoter layer (10), in particular made of metal, a lower ceramic layer (11), which rests directly on the adhesion promoter layer (10) or the oxide layer thereof, and an outermost ceramic layer (12) which rests directly on the lower ceramic layer (11), the lower ceramic layer (11) having a machined structured surface (21).

Description

[0001] 2024 PF00817

[0002] 1

[0003] Component with multi-layer thermal insulation layer and modified bonding layer and method

[0004] The invention relates to components with a multi-layered ceramic thermal insulation layer and a modified ceramic bonding layer, as well as a method for this.

[0005] Components for high-temperature applications, such as in turbines, especially gas turbines, have protective layers against corrosion and heat.

[0006] Such components have a substrate that can be ceramic or metallic.

[0007] In the case of ceramics, this is in particular a CMC matrix, and in the case of metals, a nickel-based superalloy - see e.g. US 6,231,692 pp.

[0008] Often, an adhesion promoter layer is applied to the substrate, which not only enables improved bonding of a ceramic layer to the substrate, but also prevents corrosion and oxidation of the substrate.

[0009] In the case of metallic alloys, such as nickel-based alloys in particular, these are so-called MCrAlY alloys - see e.g. EP 1 306 454 Bl - for these coatings.

[0010] Often, two-layer ceramic thermal barrier coatings – see, for example, EP 2 733 236 Al – are used to optimally utilize the properties of different ceramic materials. Ceramic materials with high temperature resistance and phase stability at high and varying temperatures, such as fully stabilized zirconia, exhibit too large a difference in their coefficients of thermal expansion to be applied directly to a substrate or the bonding agent layer.2024 PF00817

[0011] 2

[0012] To apply, an additional ceramic bonding layer is applied. This creates an interface between the two ceramic layers.

[0013] Sometimes the upper ceramic layer chips off due to insufficient adhesion to the lower ceramic bonding layer.

[0014] It is therefore the purpose of the invention to solve the problem mentioned above.

[0015] The problem is solved by a component according to claim 1 and a method according to claim 9.

[0016] The dependent claims list further advantageous measures which can be combined in any way to achieve further advantages in a synergistic manner.

[0017] They show

[0018] Figure 1 shows a component with a two-layer ceramic thermal insulation layer.

[0019] Figure 2 shows a process step for processing a lower ceramic thermal insulation layer.

[0020] Figures 3, 4, 5, 6 show different embodiments of the ceramic surface of the lower ceramic

[0021] thermal insulation layer,

[0022] Figure 7 shows a final manufacturing step.

[0023] The description and figures represent only exemplary embodiments of the invention. 2024 PF00817

[0024] 3

[0025] Figure 1 shows a component 1 ' according to the prior art, which has an entire, two-layer thermal insulation layer 4 ' .

[0026] A metallic adhesion promoter layer 10 is applied to a metallic substrate 7, preferably a nickel- or cobalt-based superalloy, as is also used in the invention 7, 10.

[0027] In the case of ceramics, the substrate is in particular a CMC matrix, made of aluminum oxide or cermets.

[0028] This adhesion promoter layer 10 preferably comprises an alloy based on NiCoCrAlY, not only in the prior art but also for the invention, e.g. NiCoCrAlY-Re, NiCoCrAl-Ta-Si, NiCoCrAlY-Ta, ....

[0029] Often, the metallic adhesion promoter layer 10 already forms an oxide layer (TGO) during manufacturing or initially in use, which is also a ceramic layer, but is not part of a lower ceramic layer 11 '.

[0030] The lower ceramic layer 11 ' lies directly on the metallic adhesion promoter layer 10 or on the oxide layer (TGO) of the metallic adhesion promoter layer 10.

[0031] The two-layer thermal insulation layer 4' is applied to this metallic adhesion promoter layer 10 or to the TGO.

[0032] The two-layer thermal insulation layer 4' has a lower 2024 PF00817

[0033] 4

[0034] ceramic layer 11 ' and an upper ceramic layer 12 ' on .

[0035] Figure 2 shows a step in the production of a component 1 according to the invention, in which the lower ceramic layer 11' has already been applied with a surface 20 which is machined by a machining machine 15.

[0036] This can be a high-pressure device 15 that emits water jets 18 with or without abrasive particles, or a laser 15 that emits laser beams 18.

[0037] In this processing step, material is selectively removed from surface 20.

[0038] A structured surface 21 is created for the lower ceramic layer 11.

[0039] The surface 21 can have truncated pyramids (Figure 3, 21') with triangular, square or round cross-section, bump-like elevations (Figure 4, 21''), pyramids with triangular or square cross-section (Figure 5, 21'''') or cavities (Figure 6, 21'''''') with undercuts.

[0040] Other shapes and / or cross-sections or variations thereof on a surface are also conceivable.

[0041] Likewise, it is not necessary to process the entire surface 20.

[0042] In the case of a turbine blade, these would only be the areas subject to particularly high stress, such as the leading edge.

[0043] The lower ceramic layer is 11 , 11 ' , 11 '' , . . preferably thinner than an upper ceramic layer 2024 PF00817

[0044] 5

[0045] Layer 12 (Fig. 7) , i.e. it is at least 20%, in particular 30% thinner .

[0046] Preferably, the lower ceramic layer 11 , 11 ' , 11 '' , . . partially stabilized zirconium oxide is applied.

[0047] In Figure 7, at least the second ceramic thermal insulation layer 12 is then applied to such a machined surface 21, which has a greatly enlarged contact area to the lower thermal insulation layer 11 , 11 ' , 11 '' , . . .

[0048] The second thermal insulation layer 12 lies directly on the lower ceramic layer 11 , 11 ' , 11 '' , . . on .

[0049] In particular, this is the outermost thermal insulation layer 12 of the entire thermal insulation layer 4 .

[0050] Likewise, further ceramic layers can be applied to the second thermal insulation layer 12, thus creating a multi-layer thermal insulation layer: 11- 11-12... or 11 -12 - 11-12 , where “11” stands for a thermal insulation layer with a processed surface and “12” for a thermal insulation layer with an unprocessed surface .

[0051] In this process, at least one or the respective underlying thermal insulation layer may, but does not have to, have a treatment as described in Figures 3-6.

[0052] Through these structures and processing, a component 1 with a multi-layered thermal insulation layer 4 is achieved, in which the uppermost or top ceramic layer 12 does not flake off.

[0053] Known from the state of the art are methods in which, in one of the last layers for the lower ceramic thermal insulation layer, other parameters of the plasma nozzles or 2024 PF00817 are used.

[0054] 6

[0055] Other nozzles or other, coarser powders may be used to achieve a higher roughness, using the same material as for the lower thermal insulation layer.

[0056] This is not necessary here.

Claims

2024 PF00817 Patent claims 1. Component ( 1 ) with at least two layers of thermal insulation ( 4 ), in particular only two layers of thermal insulation ( 4 ), at least having a substrate ( 7 ) , in particular a metallic substrate ( 4 ) , an adhesion promoter layer ( 10 ) on the substrate ( 4 ) in particular made of metal , at least one lower ceramic layer ( 11 ) , in particular only one lower ceramic layer ( 11 , 11 ' , 11 '' , . . ) , which lies directly on the adhesion promoter layer ( 10 ) or its oxide layer as well as at least one more , especially outermost ceramic layer ( 12 ) , which lies directly on the lower ceramic layer ( 11 , 11 ' , 11 '' , . . ) , wherein the lower ceramic layer ( 11 , 11 ' , 11 '' , . . ) has a machined structured surface ( 21 , 21 ' , 21 '' , ... ) .

2. Component according to claim 1 , in which the lower ceramic layer ( 11 ' ) has truncated pyramids on its surface ( 21 ' ).

3. Component according to claim 1 or 2 , in which the lower ceramic layer ( 11 '' ) has a bumpy surface on its surface ( 21 '' ).

4. Component according to claim 1, 2 or 3, where the structured surface ( 21 '' '' ) of the lower ceramic layer ( 11 '' '' ) is formed by pyramids with 2024 PF00817 formed on a triangular or square base.

5. Component according to claim 1, 2, 3, or 4, in which the structured surface ( 21 ' ' ' ) of the lower ceramic layer ( 11 ' ' ' ) is formed by cavities with undercuts .

6. Component according to one or more of the preceding claims, where only a two-layer thermal insulation layer ( 4 ) is present .

7. Component according to claim 6 , in which the lower ceramic layer ( 11 ) is thinner than an upper ceramic layer ( 12 ), in particular it ( 11 ) is at least 20% thinner, in particular 30% thinner, made thinner.

8. Component according to claim 6 or 7 , in which the lower ceramic layer ( 11 ) contains partially stabilized s zirconium oxide .

9. Method for manufacturing a component ( 1 ) according to one or more of the preceding claims 1 to 8 , in which, in a processing step prior to the application of the outermost ceramic layer (12), the surface (20) of a lower ceramic layer is processed (11, 11', 11'', . . ) , and then a second s , especially outermost, ceramic layer ( 12 ) is applied .

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