CN108754398B - Preparation method of high-purity porous ceramic abradable seal coating - Google Patents

Preparation method of high-purity porous ceramic abradable seal coating Download PDF

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CN108754398B
CN108754398B CN201810631830.2A CN201810631830A CN108754398B CN 108754398 B CN108754398 B CN 108754398B CN 201810631830 A CN201810631830 A CN 201810631830A CN 108754398 B CN108754398 B CN 108754398B
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powder
coating
purity
ceramic
preparation
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CN108754398A (en
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于月光
沈婕
彭浩然
刘建明
侯伟骜
卢晓亮
刘通
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Bgrimm Advanced Materials Science & Technology Co ltd
BGRIMM Technology Group Co Ltd
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Bgrimm Advanced Materials Science & Technology Co ltd
BGRIMM Technology Group Co Ltd
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    • 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
    • C23C4/04—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

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Coating By Spraying Or Casting (AREA)

Abstract

The invention discloses a preparation method of a high-purity porous ceramic abradable seal coating, and belongs to the technical field of seal coatings. The high-purity porous abradable seal coating with high porosity and high bonding strength is prepared by adopting high-energy plasma spraying technology and taking high-purity ceramic powder which does not contain pore-forming agent and has bimodal grain size distribution as a raw material, so that the anti-sintering performance of the coating is effectively improved, the service temperature of the coating is further improved, and the service life of the coating is prolonged.

Description

Preparation method of high-purity porous ceramic abradable seal coating
Technical Field
The invention belongs to the technical field of sealing coatings, and relates to a preparation method of a pore-forming agent-free high-purity porous ceramic abradable sealing coating.
Background
The abradable seal coating can effectively reduce the clearance between the rotor and the stator of the engine, reduce oil consumption and improve the efficiency and the operation safety of the engine. The ceramic-based abradable seal coating has the advantages of high temperature resistance, corrosion resistance and heat insulation, is widely applied to the outer ring part of medium and high pressure turbines of aeroengines and ground gas turbines, has the application temperature of more than 1000 ℃, and is the abradable seal coating with the highest application temperature at present. As the aerospace industry develops, higher demands are placed on the performance of the seal coating. The long-term service temperature of the sealing coating is required to exceed 1050 ℃, and the sealing coating has smaller pore size, higher porosity and bonding strength.
Conventional ceramic baseThe preparation of the sealing coating usually adopts powder containing polyphenyl ester and other pore-forming agents as raw materials, the content of the pore-forming agents is generally more than 10 wt%, and meanwhile, Fe in the material2O3、SiO2、Al2O3And the content of CaO and other impurities is more than or equal to 0.5 percent. In the process of preparing the coating, because the pore-forming agent is not uniformly distributed and volatilized, a large number of connected pore defects exist in the coating, and the bonding strength and service life of the coating are low. And Fe in the coating2O3、SiO2、Al2O3And the existence of impurities such as CaO causes that the coating is easy to generate phase change and sintering problems when the coating works for a long time under the service working condition of over 1050 ℃, so that the coating is cracked and fails. In addition, the conventional plasma spraying process has low energy density and small powder treatment amount (less than 50g/min), so that the pore size of the prepared ceramic sealing coating is difficult to control and the bonding strength is low.
Disclosure of Invention
The invention aims to provide a preparation method for improving the service temperature of a ceramic abradable seal coating and keeping the characteristics of smaller pore size, higher porosity and bonding strength of the coating, thereby effectively improving the application performance of the ceramic seal coating. According to the invention, ceramic powder without pore-forming agent is used as a raw material, so that the pore uniformity of the coating is effectively improved, and the service temperature and the toughness of the coating are improved through the high-purity superfine characteristic of the material. The ceramic sealing coating with smaller pore size, higher porosity and bonding strength can be efficiently and stably prepared by a high-energy plasma spraying process.
The preparation method of the high-purity porous ceramic abradable seal coating comprises the following steps:
(1) adopting high-purity ceramic powder without pore-forming agent as raw material;
(2) carrying out double-peak grain size grading on the powder to realize the coarse and fine grain size matching of the powder;
(3) preparing a high-purity ceramic porous coating on a workpiece with a prepared bonding bottom layer by a high-energy plasma spraying process, wherein the thickness of the coating is 0.5-5 mm.
In some specific embodiments, the purity of the high-purity ceramic powder obtained in the step (1) is more than or equal to 99.5%, and the impurity content is less than or equal to 0.5%. Furthermore, the purity of the high-purity ceramic powder is more than or equal to 99.9 percent, and the content of impurities is less than or equal to 0.1 percent.
In some embodiments, the high purity ceramic powder particles of step (1) have a particle size of 5 to 1000 nm. Further, the particle size of the high-purity ceramic powder particles is 10-200 nm.
In some embodiments, the high-purity ceramic powder in step (1) is one or more of zirconia, yttria, dysprosia, ytterbia, gadolinia, lanthana, ceria, and magnesia.
In some embodiments, the bimodal size grading of the powder in step (2) is performed by mixing coarse powder and fine powder according to a certain ratio, wherein the peak particle size of the coarse powder is 75-400 μm, and the peak particle size of the fine powder is 10-75 μm. Furthermore, the coarse powder accounts for 60-80 wt%, and the fine powder accounts for 40-20 wt%.
In some embodiments, the high-energy plasma spraying process in step (3) is spraying with a high-power or cascade plasma spray gun in an atmosphere, low pressure or inert gas atmosphere.
In some embodiments, the porosity of the ceramic porous sealing coating in the step (3) is 15-45%, and the pore size is 5-40 μm.
Compared with the traditional preparation process of combining ceramic powder raw materials containing a large amount of pore-forming agents with conventional atmospheric plasma spraying, the preparation method of the high-purity porous ceramic abradable seal coating has the characteristics of uniform and controllable pore size of the coating, high bonding strength, simple process and the like.
Drawings
FIG. 1 is a schematic illustration of a bimodal particle size distribution of a ceramic powder according to an embodiment of the present invention.
FIG. 2 is an SEM image of the cross-sectional profile of a ceramic abradable seal coating made in accordance with embodiments of the present invention.
FIG. 3 is a partial SEM image of a cross-section of a ceramic abradable seal coating made in accordance with embodiments of the invention.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.
The specific embodiment of the invention provides a preparation method of a high-purity porous ceramic abradable seal coating, which comprises the following steps:
step (1): high-purity ceramic powder without any pore-forming agent is used as raw material powder of the ceramic abradable seal coating. Wherein the purity of the ceramic powder is more than or equal to 99.9 percent, the impurity content is less than or equal to 0.1 percent, the primary granularity of the ceramic powder is 5-1000 nm, and the typical granularity of the ceramic powder is 10-200 nm. The ceramic powder comprises one or more of zirconia, yttria, dysprosia, ytterbium oxide, gadolinium oxide, lanthanum oxide, cerium oxide and magnesium oxide.
Step (2): grading the ceramic powder without the pore-forming agent according to a specific particle size ratio, and fully and uniformly mixing to obtain the ceramic sealing coating powder raw material with the bimodal particle size grading characteristic. Wherein the peak value of the particle size of the coarse powder is 75-400 μm, the peak value of the particle size of the fine powder is 10-75 μm, the typical particle size collocation proportion is that the coarse powder accounts for 60-80 wt%, and the fine powder accounts for 40-20 wt%.
And (3) preparing a ceramic porous sealing coating on a workpiece with a prepared bonding bottom layer by taking the powder obtained in the step (2) as a raw material and adopting a three-anode or three-cathode high-energy plasma spraying process in the atmosphere, low pressure or inert gas protective atmosphere, wherein the thickness of the coating is 0.5-5 mm, the porosity is 15-45%, and the typical pore size is controllable from 5 to 40 microns.
The following detailed description of embodiments of the invention will be made with reference to the accompanying drawings.
Example 1
Step (1): high-purity yttria-stabilized zirconia powder without any pore-forming agent is used as raw material powder of the ceramic abradable seal coating. Wherein the purity of the ceramic powder is more than or equal to 99.93 percent, and the primary granularity of the ceramic powder is 30-80 nm.
Step (2): grading the ceramic powder without the pore-forming agent according to a specific particle size ratio, and fully and uniformly mixing to obtain the ceramic sealing coating powder raw material with the bimodal particle size grading characteristic. Wherein the ceramic powder with the peak value of the coarse powder particle size of 75-100 μm accounts for 80 wt%, and the ceramic powder with the peak value of the fine powder particle size of 15-37 μm accounts for 20%, as shown in figure 1.
And (3) preparing a ceramic porous sealing coating on the workpiece with the prepared bonding bottom layer by taking the powder obtained in the step (2) as a raw material and adopting a three-anode high-energy plasma spraying process in an atmospheric atmosphere, wherein the thickness of the prepared ceramic porous sealing coating is 1.5mm, the porosity is 31%, the pore size is 5-40 mu m, and the bonding strength of the coating is 9.0MPa as shown in the attached drawings 2-3.
Example 2
Step (1): high-purity dysprosium oxide stabilized zirconia powder without any pore-forming agent is used as raw material powder of the ceramic abradable seal coating. Wherein the purity of the ceramic powder is more than or equal to 99.92 percent, and the primary granularity of the ceramic powder is 40-90 nm.
Step (2): grading the ceramic powder without the pore-forming agent according to a specific particle size ratio, and fully and uniformly mixing to obtain the ceramic sealing coating powder raw material with the bimodal particle size grading characteristic. Wherein the ceramic powder with the peak value of the grain diameter of the coarse powder being 75-150 mu m accounts for 70 wt%, and the ceramic powder with the peak value of the grain diameter of the fine powder being 15-45 mu m accounts for 30 wt%.
And (3) preparing a ceramic porous sealing coating on the workpiece with the prepared bonding bottom layer by taking the powder obtained in the step (2) as a raw material and adopting a three-anode high-energy plasma spraying process in an atmospheric atmosphere, wherein the thickness of the prepared coating is 2.5mm, the porosity is 35%, the pore size is 5-40 mu m, and the bonding strength of the coating is 8.6 MPa.
Example 3
Step (1): high-purity ytterbium oxide stabilized zirconia powder without any pore-forming agent is used as raw material powder of the ceramic abradable seal coating. Wherein the purity of the ceramic powder is more than or equal to 99.95 percent, and the primary granularity of the ceramic powder is 10-300 nm.
Step (2): grading the ceramic powder without the pore-forming agent according to a specific particle size ratio, and fully and uniformly mixing to obtain the ceramic sealing coating powder raw material with the bimodal particle size grading characteristic. Wherein the ceramic powder with the peak value of the grain diameter of the coarse powder being 75-150 mu m accounts for 60 wt%, and the ceramic powder with the peak value of the grain diameter of the fine powder being 10-45 mu m accounts for 40%.
And (3) preparing a ceramic porous sealing coating on the workpiece with the prepared bonding bottom layer by taking the powder obtained in the step (2) as a raw material and adopting a three-cathode high-energy plasma spraying process in an atmospheric atmosphere, wherein the thickness of the prepared coating is 2.3mm, the porosity is 28%, the pore size is 5-40 mu m, and the bonding strength of the coating is 9.4 MPa.
Example 4
Step (1): high-purity ytterbium, gadolinium and yttrium co-stabilized zirconia powder without any pore-forming agent is used as raw material powder of the ceramic abradable seal coating. Wherein the purity of the ceramic powder is more than or equal to 99.94%, and the primary granularity of the ceramic powder is 10-50 nm.
Step (2): grading the ceramic powder without the pore-forming agent according to a specific particle size ratio, and fully and uniformly mixing to obtain the ceramic sealing coating powder raw material with the bimodal particle size grading characteristic. Wherein the ceramic powder with the particle size peak value of 100-450 μm accounts for 75 wt%, and the ceramic powder with the particle size peak value of 20-53 μm accounts for 25%
And (3) preparing a ceramic porous sealing coating on the workpiece with the prepared bonding bottom layer by taking the powder obtained in the step (2) as a raw material and adopting a three-anode high-energy plasma spraying process in an atmospheric atmosphere, wherein the thickness of the prepared coating is 1.6mm, the porosity is 28%, the pore size is 5-40 mu m, and the bonding strength of the coating is 9.8 MPa.
Example 5
Step (1): high-purity lanthanum zirconate powder without any pore-forming agent is used as raw material powder of the ceramic abradable seal coating. Wherein the purity of the ceramic powder is more than or equal to 99.95 percent, and the primary granularity of the ceramic powder is 50-700 nm.
Step (2): grading the ceramic powder without the pore-forming agent according to a specific particle size ratio, and fully and uniformly mixing to obtain the ceramic sealing coating powder raw material with the bimodal particle size grading characteristic. Wherein the ceramic powder with the peak value of the grain diameter of the coarse powder being 75-350 mu m accounts for 65 wt%, and the ceramic powder with the peak value of the grain diameter of the fine powder being 25-53 mu m accounts for 20 wt%.
And (3) preparing a ceramic porous sealing coating on the workpiece with the prepared bonding bottom layer by taking the powder obtained in the step (2) as a raw material and adopting a three-anode high-energy plasma spraying process in an atmospheric atmosphere, wherein the thickness of the prepared coating is 2.0mm, the porosity is 25%, the pore size is 5-40 mu m, and the bonding strength of the coating is 8.9 MPa.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.

Claims (7)

1. The preparation method of the high-purity porous ceramic abradable seal coating is characterized by comprising the following steps:
(1) adopting high-purity ceramic powder without pore-forming agent as raw material;
(2) mixing the coarse powder and the fine powder according to a certain proportion, wherein the peak value of the particle size of the coarse powder is 75-400 mu m, and the peak value of the particle size of the fine powder is 10-75 mu m, so that the coarse and fine particle size matching of the powder is realized;
(3) preparing a high-purity ceramic porous coating on a workpiece with a prepared bonding bottom layer by a high-energy plasma spraying process, wherein the thickness of the coating is 0.5-5 mm.
2. The preparation method according to claim 1, wherein in the step (1), the purity of the high-purity ceramic powder is more than or equal to 99.5 percent, and the impurity content is less than or equal to 0.5 percent.
3. The preparation method of claim 2, wherein the purity of the high-purity ceramic powder is more than or equal to 99.9%, and the impurity content is less than or equal to 0.1%.
4. The preparation method according to claim 1, wherein in the step (1), the high-purity ceramic powder is one or more of zirconia, yttria, dysprosia, ytterbia, gadolinia, lanthana, ceria and magnesia.
5. The method according to claim 1, wherein the coarse powder is 60 to 80 wt%, and the fine powder is 40 to 20 wt%.
6. The method of claim 1, wherein in step (3), the high energy plasma spray process is spraying using a high power or cascade plasma spray gun in an atmospheric, low pressure or inert gas protected environment.
7. The preparation method according to claim 1, wherein in the step (3), the high purity ceramic porous coating has a porosity of 15 to 45% and a pore size of 5 to 40 μm.
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CN114411085B (en) * 2021-11-25 2024-09-06 矿冶科技集团有限公司 Preparation method of dense thick thermal barrier coating
CN117568737B (en) * 2024-01-12 2024-05-28 北矿新材科技有限公司 Coating with high thermal shock resistance and high abrasion resistance, preparation method thereof, engine and aircraft

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Publication number Priority date Publication date Assignee Title
CN102482168A (en) * 2009-10-14 2012-05-30 赢创德固赛有限公司 Process for the infiltration of porous ceramic components
CN107653432A (en) * 2017-09-28 2018-02-02 中国航发动力股份有限公司 A kind of high energy plasma spraying prepares the process of thermal barrier coating

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DE102016210378A1 (en) * 2016-06-10 2017-12-14 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. CIRCONOXIDE CERAMIC, CELLULAR MATERIAL THEREOF AND METHOD FOR THE PRODUCTION OF ZIRCONOXIDE CERAMIC
CN107805775A (en) * 2017-09-28 2018-03-16 中国航发动力股份有限公司 A kind of high-temperature abradable seal coating and preparation method thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102482168A (en) * 2009-10-14 2012-05-30 赢创德固赛有限公司 Process for the infiltration of porous ceramic components
CN107653432A (en) * 2017-09-28 2018-02-02 中国航发动力股份有限公司 A kind of high energy plasma spraying prepares the process of thermal barrier coating

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