CN114293132B - Method for improving bonding strength of environmental barrier coating by utilizing nano modified silicon bonding layer - Google Patents
Method for improving bonding strength of environmental barrier coating by utilizing nano modified silicon bonding layer Download PDFInfo
- Publication number
- CN114293132B CN114293132B CN202111662233.4A CN202111662233A CN114293132B CN 114293132 B CN114293132 B CN 114293132B CN 202111662233 A CN202111662233 A CN 202111662233A CN 114293132 B CN114293132 B CN 114293132B
- Authority
- CN
- China
- Prior art keywords
- barrier coating
- powder
- bonding layer
- environmental barrier
- spraying
- 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.)
- Active
Links
- 238000000576 coating method Methods 0.000 title claims abstract description 104
- 239000011248 coating agent Substances 0.000 title claims abstract description 97
- 230000004888 barrier function Effects 0.000 title claims abstract description 83
- 238000000034 method Methods 0.000 title claims abstract description 66
- 230000007613 environmental effect Effects 0.000 title claims abstract description 61
- 239000000843 powder Substances 0.000 claims abstract description 54
- 239000011863 silicon-based powder Substances 0.000 claims abstract description 49
- 238000010438 heat treatment Methods 0.000 claims abstract description 47
- 238000000498 ball milling Methods 0.000 claims abstract description 34
- 239000003607 modifier Substances 0.000 claims abstract description 24
- 238000007750 plasma spraying Methods 0.000 claims abstract description 24
- 239000000758 substrate Substances 0.000 claims abstract description 15
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052863 mullite Inorganic materials 0.000 claims abstract description 13
- 239000011159 matrix material Substances 0.000 claims abstract description 12
- 238000005507 spraying Methods 0.000 claims description 49
- 230000008569 process Effects 0.000 claims description 35
- 239000000463 material Substances 0.000 claims description 15
- 238000000227 grinding Methods 0.000 claims description 11
- 239000011230 binding agent Substances 0.000 claims description 10
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 8
- 239000000853 adhesive Substances 0.000 claims description 8
- 230000001070 adhesive effect Effects 0.000 claims description 8
- 239000011812 mixed powder Substances 0.000 claims description 8
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 8
- 238000007873 sieving Methods 0.000 claims description 6
- 239000011153 ceramic matrix composite Substances 0.000 claims description 5
- 238000001035 drying Methods 0.000 claims description 4
- 238000005259 measurement Methods 0.000 claims description 4
- 238000002156 mixing Methods 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 4
- 238000012216 screening Methods 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 abstract description 5
- 230000002035 prolonged effect Effects 0.000 abstract description 5
- 239000010410 layer Substances 0.000 description 85
- 238000000724 energy-dispersive X-ray spectrum Methods 0.000 description 12
- 229910001404 rare earth metal oxide Inorganic materials 0.000 description 10
- 238000005260 corrosion Methods 0.000 description 9
- 230000007797 corrosion Effects 0.000 description 9
- 229910052760 oxygen Inorganic materials 0.000 description 8
- 230000006872 improvement Effects 0.000 description 6
- 230000008859 change Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 229910004298 SiO 2 Inorganic materials 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 239000002105 nanoparticle Substances 0.000 description 4
- 239000002344 surface layer Substances 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 230000003628 erosive effect Effects 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 2
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 230000002708 enhancing effect Effects 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 239000012790 adhesive layer Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 230000012010 growth Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 238000009991 scouring Methods 0.000 description 1
- 229910000601 superalloy Inorganic materials 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- 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
Abstract
A method for improving the bonding strength of an environmental barrier coating by utilizing a nano modified silicon bonding layer relates to a method for improving the bonding strength of the environmental barrier coating. The method aims at solving the problems that an Si bonding layer in the existing environment barrier coating is easy to fall off and lose efficacy, stress is generated at an interface, and the bonding strength of the environment barrier coating is low. The method comprises the following steps: wet ball milling to prepare modified Si powder with nanometer CeO as modifier 2 Powder and nano HfO 2 Powder, adopting plasma spraying to prepare Si bonding layer, mullite layer and Yb on the matrix in turn 2 SiO 5 The layer provides an environmental barrier coating. According to the invention, through the modified Si bonding layer, part of components at the interface are alloyed, and residual stress generated in the preparation process of the substrate and the coating is released through subsequent heat treatment, so that the bonding strength of an environment barrier coating system is improved, and the service life of the environment barrier coating is prolonged. The invention is suitable for preparing the environment barrier coating.
Description
Technical Field
The invention belongs to the technical field of preparation of thermal protection coatings of aeroengines and gas turbines, and particularly relates to a method for improving the bonding strength of an environmental barrier coating.
Background
The high thrust weight of the engine puts higher requirements on the service temperature of the hot end component than the service limit of the traditional Ni-based superalloy. The ceramic matrix composite material, especially the SiC matrix composite material, is hopeful to replace high-temperature alloy due to the advantages of small density, high thermal stability and the like, and becomes a main high-temperature structural material of a hot end part of an engine. However, siC is susceptible to molten salt corrosion and water oxygen corrosion in high temperature service environments and under high velocity gas flow washout. Wherein, the water oxygen corrosion is most serious, which seriously shortens the service life of the hot end component of the engine. Thus, environmental barrier coatings have been developed in the 90 s of the 20 th century.
The environmental barrier coating is a barrier for blocking the high-temperature structural material from severe environments such as high temperature, high-speed airflow, molten salt and the like. The development of environmental barrier coatings is continually optimized in composition and structure. Structurally, the first two layers (bonding layer, surface layer) are developed into a three-layer structure (bonding layer, middle layer, surface layer) which is the best. Wherein the bonding layer is a transition layer between the substrate and the coating, and the selection of the bonding layer is critical to the performance of the environmental barrier coating system. The adhesive layer is selected according to the following principles: (1) The composite material does not react with a matrix, and has higher chemical compatibility; (2) The high-temperature stability is high, and the phase change is not easy to occur at the working temperature; (3) The thermal expansion coefficient matched with the matrix is smaller in interface stress; (4) Low O 2 /O 2- Permeability. Based on the principle, the materials of the bonding layer undergo three major changes. The main component of the first-generation bonding layer is mullite (3 Al 2 O 3 ·2SiO 2 ). Mullite as a bonding layer exposes some drawbacks during use. In one aspect, siO in mullite 2 React with water vapor in the high velocity gas stream to form Si (OH) in the gas phase 4 A large number of holes are formed at the interface between the bonding layer and the surface layer under the scouring action of high-speed air flow, and the surface layer is easy to fall off. On the other hand, the powder feed melted at high temperature in the coating preparation process impacts the surface of the normal-temperature matrix and is rapidly cooled in a short time, so that amorphous phase is generated in mullite, and under the high-temperature service environment, the amorphous phase changes to crystalline phase to cause volume change, and cracks are initiated. Later, mullite structures were more applied to the middle layer of environmental barrier coating systems. The main component of the second-generation bonding layer is BSAS (1-xBaO xSrO 2 ·Al 2 O 3 ·2SiO 2 ) A coating or a layer of a BSAS based hybrid material. However, the BSAS coating is easy to volatilize, and the loss can reach 10 under the service environment of high temperature and high-speed air flow flushing 2 μm; in addition, siO which is easy to be combined with the surface of the matrix in the use process of the BSAS coating 2 The reaction is carried out to generate a low-melting-point glass phase, so that the loss of the matrix is increased, and meanwhile, the bonding strength between the bonding layer and the interface of the matrix is greatly reduced. The third generation bonding layer adopts Si bonding layer, which is also the current ringThe most commonly used tie layers for environmental barrier coatings. However, si bonding layer is easy to generate thermally grown SiO during use 2 On the one hand O in thermal growths 2 O and O 2- The permeability of the outer layer is high, and O of the outer layer is easy to permeate into the inner layer through the thermally grown substance layer, so that the bonding layer is fallen off and fails. On the other hand, siO 2 Phase changes occur at a certain temperature and the resulting volume expansion causes stresses at the interface. Modification of the Si tie layer has therefore been an important direction in the research and development of environmental barrier coatings.
Disclosure of Invention
The invention provides a method for improving the bonding strength of an environmental barrier coating by utilizing a nano modified silicon bonding layer, which aims to solve the problems that an Si bonding layer in the existing environmental barrier coating is easy to fall off and lose efficacy and causes stress at an interface, so that the bonding strength of the environmental barrier coating is low.
The method for improving the bonding strength of the environmental barrier coating by utilizing the nano modified silicon bonding layer comprises the following steps:
step one, preparing modified Si powder by wet ball milling:
mixing a modifier with Si powder to obtain mixed powder, ball-milling the mixed powder, adding a binder in the ball-milling process, ball-milling to obtain pug, drying, grinding and sieving the pug to obtain modified Si powder;
the modifier is nano CeO 2 Powder and nano HfO 2 A mixture of powders in any ratio; ceO (CeO) 2 The purity of the powder is 99.99 percent, and the grain diameter is 30-60 nm; hfO (HfO) 2 The purity of the powder is 99.99 percent, and the grain diameter is 80-100 nm;
the grain diameter of the Si powder is 40-100 mu m;
the addition amount of the modifier is 1-3% of the mass of Si powder;
the ball milling process comprises the following steps: the grinding ball selects ZrO 2 Ball, grinding ball diameter is 0.8-1.2 mm, ball material volume ratio is 1: (3-5), ball milling rotating speed is 250-350 r/min, ball milling time is 23-25 h, and binding agent is added after 11-13 h in the ball milling process;
the adhesive is polyvinyl alcohol (PVA), and the adhesive is 1.4-1.6% of the mass of the modifier; the binder is used for enhancing the adhesion of the modifier to the Si powder.
The sieving adopts a 150-200 mesh sieve;
step two, sequentially preparing a Si bonding layer, a mullite layer and Yb on the substrate by adopting plasma spraying 2 SiO 5 A layer to obtain an environmental barrier coating; the modified Si powder prepared in the first step is adopted for preparing the Si bonding layer;
the substrate is made of a ceramic matrix composite material;
the plasma spraying adopts atmospheric plasma spraying equipment;
the plasma spraying process of the Si bonding layer comprises the following steps: the spraying current is 450A, the spraying voltage is 45V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 10g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s;
the plasma spraying process of the mullite layer comprises the following steps: the spraying current is 550A, the spraying voltage is 55V, the main air flow is 120, the carrier air flow is 60, the powder feeding speed is 8g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s;
the Yb is 2 SiO 5 The plasma spraying process of the layer comprises the following steps: the spraying current is 500A, the spraying voltage is 50V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 6.3g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
And thirdly, performing heat treatment on the environment barrier coating to finish the process.
The heat treatment process of the environmental barrier coating comprises the following steps: the heat treatment temperature is 900-1300 ℃, the heat treatment time is 1.8-2.2 h, and the heating rate is 4.8-5.2 ℃/min.
The principle and beneficial effects of the invention are as follows:
according to the invention, through the modified Si bonding layer, part of components at the interface are alloyed, and residual stress generated in the preparation process of the substrate and the coating is released through subsequent heat treatment, so that the bonding strength of an environment barrier coating system is improved, and the service life of the environment barrier coating is prolonged.
The invention adopts nano CeO 2 Powder and nano HfO 2 Modification of Si powder by powder rare earth oxide, etcLattice structure change of Si bonding layer finally obtained after ion spraying, thereby realizing the relief of O 2- O and O 2 Penetration into the matrix. At the same time rare earth oxide and thermally grown SiO 2 The reaction generates corresponding silicate, thereby inhibiting the thermally grown SiO 2 The phase change of the Si bonding layer is avoided, the stress at the interface is avoided due to volume expansion, the generation of cracks is reduced, the service temperature and the bonding strength of the Si bonding layer are further improved, the interface between the Si bonding layer and the substrate is enhanced, the failure falling caused by weak interface between the substrate and the bonding layer is avoided, and the service life of the environment barrier coating is prolonged.
The rare earth oxide powder adopted by the invention is nano particles, the nano particle reinforced material shows higher total work function, the corrosion potential is obviously improved, the electronic stability is improved, the activity is reduced, and compared with the traditional micron rare earth oxide, the nano rare earth oxide powder is obviously improved in the aspects of improving the electric erosion resistance and the stress corrosion resistance of the coating, and is more suitable for being used as a modifier of the coating.
The invention adopts 3 percent HfO 2 And (3) preparing an environment barrier coating by modifying the Si bonding layer obtained by the Si powder, wherein the bonding strength of the environment barrier coating system reaches 24.83MPa after heat treatment (1300 ℃ for 2 h). The electron work function measurement value of the modified Si bonding layer in the environment barrier coating system is 4.9eV, and is also the highest value of a research system.
Drawings
FIG. 1 shows 1% CeO 2 Modified Si powder surface morphology and EDS spectrum;
FIG. 2 shows 2% CeO 2 Modified Si powder surface morphology and EDS spectrum;
FIG. 3 shows 3% CeO 2 Modified Si powder surface morphology and EDS spectrum;
fig. 4 is 1% HfO 2 Modified Si powder surface morphology and EDS spectrum;
fig. 5 is 2% HfO 2 Modified Si powder surface morphology and EDS spectrum;
fig. 6 is 3% HfO 2 Modified Si powder surface morphology and EDS spectrum;
FIG. 7 is a graph of bond strength profile of an environmental barrier coating;
FIG. 8 shows the heat treatment temperature versus CeO 2 Coating bond strength profile of the modified Si tie layer;
FIG. 9 is a graph of heat treatment temperature versus HfO 2 Coating bond strength profile of the modified Si tie layer;
fig. 10 is an electron work function test chart of Si tie layers.
Detailed Description
The technical scheme of the invention is not limited to the specific embodiments listed below, and also comprises any reasonable combination of the specific embodiments.
The first embodiment is as follows: the method for improving the bonding strength of the environmental barrier coating by utilizing the nano modified silicon bonding layer in the embodiment is carried out according to the following steps:
step one, preparing modified Si powder by wet ball milling:
mixing a modifier with Si powder to obtain mixed powder, ball-milling the mixed powder, adding a binder in the ball-milling process, ball-milling to obtain pug, drying, grinding and sieving the pug to obtain modified Si powder;
the modifier is nano CeO 2 Powder and nano HfO 2 A mixture of powders in any ratio; the grain diameter is 30-60 nm, and the grain diameter is 80-100 nm;
the addition amount of the modifier is 1-3% of the mass of Si powder;
the adhesive is polyvinyl alcohol (PVA), and the adhesive is 1.4-1.6% of the mass of the modifier; the binder is used for enhancing the adhesion of the modifier to the Si powder.
Step two, sequentially preparing a Si bonding layer, a mullite layer and Yb on the substrate by adopting plasma spraying 2 SiO 5 A layer to obtain an environmental barrier coating; the second step of plasma spraying adopts atmospheric plasma spraying equipment;
thirdly, performing heat treatment on the environmental barrier coating;
the heat treatment process of the environmental barrier coating comprises the following steps: the heat treatment temperature is 900-1300 ℃, the heat treatment time is 1.8-2.2 h, and the heating rate is 4.8-5.2 ℃/min.
The present embodiment has the following advantageous effects:
according to the embodiment, the Si bonding layer is modified to alloy part of components at the interface, and residual stress generated in the preparation process of the substrate and the coating is released through subsequent heat treatment, so that the bonding strength of an environment barrier coating system is improved, and the service life of the environment barrier coating is prolonged.
The embodiment adopts nano CeO 2 Powder and nano HfO 2 Si powder is modified by the powder rare earth oxide, and the lattice structure of the Si bonding layer finally obtained after plasma spraying is changed, so that O is relieved 2- O and O 2 Penetration into the matrix. At the same time rare earth oxide and thermally grown SiO 2 The reaction generates corresponding silicate, thereby inhibiting the thermally grown SiO 2 The phase change of the Si bonding layer is avoided, the stress at the interface is avoided due to volume expansion, the generation of cracks is reduced, the service temperature and the bonding strength of the Si bonding layer are further improved, the interface between the Si bonding layer and the substrate is enhanced, the failure falling caused by weak interface between the substrate and the bonding layer is avoided, and the service life of the environment barrier coating is prolonged.
The rare earth oxide powder adopted in the embodiment is nano particles, the nano particle reinforced material shows a higher total work function, the corrosion potential is obviously improved, the electronic stability is improved, the activity is reduced, and compared with the traditional micron rare earth oxide, the nano rare earth oxide powder is obviously improved in the aspects of improving the electric erosion resistance and the stress corrosion resistance of the coating, and is more suitable for serving as a modifier of the coating.
The present embodiment employs 3% HfO 2 And (3) preparing an environment barrier coating by modifying the Si bonding layer obtained by the Si powder, wherein the bonding strength of the environment barrier coating system reaches 24.83MPa after heat treatment (1300 ℃ for 2 h). The electron work function measurement value of the modified Si bonding layer in the environment barrier coating system is 4.9eV, and is also the highest value of a research system.
The second embodiment is as follows: the first difference between this embodiment and the specific embodiment is that: the grain diameter of the Si powder in the step one is 40-100 mu m.
And a third specific embodiment: this embodiment differs from the first or second embodiment in that: the ball milling process comprises the following steps: the grinding ball selects ZrO 2 The diameter of the ball is 0.8-1.2 mm,the volume ratio of the ball materials is 1: (3-5), ball milling rotating speed is 250-350 r/min, ball milling time is 23-25 h, and binding agent is added after 11-13 h in the ball milling process.
The specific embodiment IV is as follows: this embodiment differs from one of the first to third embodiments in that: the screening in the first step adopts a 150-200 mesh screen.
Fifth embodiment: this embodiment differs from one to four embodiments in that: and step two, the substrate is made of a ceramic matrix composite material.
Specific embodiment six: this embodiment differs from one of the first to fifth embodiments in that: the plasma spraying process of the Si bonding layer in the second step is as follows: the spraying current is 450A, the spraying voltage is 45V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 10g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
Seventh embodiment: this embodiment differs from one of the first to sixth embodiments in that: the plasma spraying process of the mullite layer in the second step is as follows: the spraying current is 550A, the spraying voltage is 55V, the main air flow is 120, the carrier air flow is 60, the powder feeding speed is 8g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
Eighth embodiment: this embodiment differs from one of the first to seventh embodiments in that: yb in step two 2 SiO 5 The plasma spraying process of the layer comprises the following steps: the spraying current is 500A, the spraying voltage is 50V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 6.3g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
Detailed description nine: this embodiment differs from one to eight of the embodiments in that: step one the HfO 2 The purity of the powder is 99.99%, ceO 2 The purity of the powder is 99.99%.
Detailed description ten: this embodiment differs from one of the embodiments one to nine in that: the heat treatment process of the environmental barrier coating comprises the following steps: the heat treatment temperature is 900-1300 ℃, the heat treatment time is 2 hours, and the heating rate is 5 ℃/min.
Example 1:
the method for improving the bonding strength of the environmental barrier coating by utilizing the nano modified silicon bonding layer is carried out according to the following steps:
step one, preparing modified Si powder by wet ball milling:
mixing a modifier with Si powder to obtain mixed powder, ball-milling the mixed powder, adding a binder in the ball-milling process, ball-milling to obtain pug, drying, grinding and sieving the pug to obtain modified Si powder;
the grain diameter of the Si powder is 40-100 mu m;
the ball milling process comprises the following steps: the grinding ball selects ZrO 2 Ball, grinding ball diameter is 1mm, ball material volume ratio is 1:4, ball milling rotating speed is 300r/min, ball milling time is 24h, and a binder is added after 12h in the ball milling process;
the adhesive is polyvinyl alcohol, and the adhesive is 1.5% of the mass of the modifier;
the sieving adopts a 150-200 mesh sieve;
the modifier and the addition amount are divided into groups of: 1. CeO (CeO) 2 The adding amount of the powder is 1% of the mass of Si powder; 2. CeO (CeO) 2 The adding amount of the powder is 2% of the mass of Si powder; 3. CeO (CeO) 2 The adding amount of the powder is 3% of the mass of Si powder; 4. HfO (HfO) 2 The adding amount of the powder is 1% of the mass of Si powder; 5. HfO (HfO) 2 The adding amount of the powder is 2% of the mass of Si powder; 6. HfO (HfO) 2 The adding amount of the powder is 3% of the mass of Si powder; wherein, ceO 2 The purity of the powder is 99.99 percent, and the grain diameter is 30-60 nm; hfO (HfO) 2 The purity of the powder is 99.99 percent, and the grain diameter is 80-100 nm; the particle size of the unmodified Si powder is 40-100 mu m;
FIG. 1 shows 1% CeO 2 Modified Si powder surface morphology and EDS spectrum; FIG. 2 shows 2% CeO 2 Modified Si powder surface morphology and EDS spectrum; FIG. 3 shows 3% CeO 2 Modified Si powder surface morphology and EDS spectrum; fig. 4 is 1% HfO 2 Modified Si powder surface morphology and EDS spectrum; fig. 5 is 2% HfO 2 Modified Si powder surface morphology and EDS spectrum; fig. 6 is 3% HfO 2 Modified Si powder surface morphology and EDS spectrum;
as can be seen in fig. 1-3, most of CeO 2 The modifier is uniformly distributed on the surface of the Si powder, and the PVA added in the ball milling process is slightly adhered on the surface of the Si powder. As can be seen in fig. 4-6, most of HfO 2 The particle size of the modifier is smaller than 1 mu m, and the modifier is uniformly distributed on the surface of Si powder.
Step two, preparing Si bonding layer (thickness is 60-100 μm), mullite layer (thickness is 40-80 μm) and Yb on the substrate sequentially (from inside to outside) by using 7 groups of powder obtained in the step one by adopting plasma spraying 2 SiO 5 A layer (thickness of 80-120 μm) to obtain an environmental barrier coating;
the substrate is made of a ceramic matrix composite material; the plasma spraying adopts an atmospheric plasma spraying coating device; the plasma spraying process of the Si bonding layer comprises the following steps: the spraying current is 450A, the spraying voltage is 45V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 10g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s; the plasma spraying process of the mullite layer comprises the following steps: the spraying current is 550A, the spraying voltage is 55V, the main air flow is 120, the carrier air flow is 60, the powder feeding speed is 8g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s; the Yb is 2 SiO 5 The plasma spraying process of the layer comprises the following steps: the spraying current is 500A, the spraying voltage is 50V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 6.3g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
By testing the bonding strength of the environmental barrier coating system, ceO is determined 2 /HfO 2 Effect of additive amount on coating bond strength, fig. 7 is a graph of bond strength of environmental barrier coating; as shown in fig. 7, the bonding strength of the environmental barrier coating system of the unmodified Si bonding layer is about 10MPa, and the bonding strength of the environmental barrier coating system is obviously improved with the addition of the modifier. Wherein, 1% CeO is added 2 And 2% CeO 2 The bond strengths of the modified environmental barrier coating systems were 15MPa and 16.5MPa, respectively. With 1% CeO 2 And 2% CeO 2 The modification is compared with adding HfO with the same mass fraction 2 The bond strength of the modified environmental barrier coating system is not very different. However, the phasesCompared with 3% CeO 2 Modified, 3% HfO 2 The bonding strength of the modified environment barrier coating system is obviously improved to 18.59MPa. In the bonding strength test process, the fracture surfaces of the environmental barrier coating system are the interfaces of the matrix and the underlying Si bonding layer, and the important significance of the modified Si bonding layer is just described.
Thirdly, performing heat treatment on the environmental barrier coating obtained in the second step;
the heat treatment process of the environmental barrier coating comprises the following steps: the heat treatment temperature is 900 ℃,1100 ℃,1300 ℃, the heat treatment time is 2 hours, and the heating rate is 5 ℃/min.
FIG. 8 shows the heat treatment temperature versus CeO 2 Coating bond strength profile for modified Si bond coat, FIG. 9 is a plot of heat treatment temperature versus HfO 2 As can be seen from fig. 8 and 9, the bonding strength of the modified Si tie layer was improved in different degrees with the increase in the heat treatment temperature for the same modified environmental barrier coating, while comparing the environmental barrier coating (room temperature) obtained in the second step without heat treatment. For CeO 2 The coating of the modified Si bonding layer has more uniform improvement of bonding strength along with the improvement of the heat treatment temperature. Three kinds of CeO 2 The coatings of the modified Si tie layers all achieved the highest bond strength at 1300 ℃. Wherein, 3% CeO 2 The environmental barrier coating system of the modified Si bonding layer achieves the highest bonding strength after 1300 ℃ heat treatment, which is 23.60MPa. For HfO 2 The coating of the modified Si bonding layer has even improvement of bonding strength at 900 ℃ and 1100 ℃, and has great improvement of bonding strength when the heat treatment temperature is increased to 1300 ℃. Three kinds of HfO 2 The coatings of the modified Si tie layers all achieved the highest bond strength at 1300 ℃. Wherein, 3% HfO 2 The environmental barrier coating system of the modified Si bonding layer achieves the highest bonding strength after 1300 ℃ heat treatment, which is 24.83MPa.
The four environmental barrier coating systems were subjected to electron work function measurements, respectively, of the environmental barrier coating of the unmodified Si tie layer, without heat treatment-Pure Si), of the heat treated (1300 ℃ C., 2 h) environmental barrier coating of the unmodified Si tie layer-Pure Si 1300 ℃ C., 2h, 3% HfO 2 Environmental barrier coating-Si (3% HfO) without heat treatment of modified Si Tie layer 2 And 3% HfO 2 Heat treatment of modified Si Tie layer (1300 ℃ C., 2 h) environmental Barrier coating-Si (3% HfO) 2 )1300℃、2h。
The measuring process is to select 200 points on the surface of the coating to measure by using a Kelvin probe system, and take the average value of the measured values. Fig. 10 is an electron work function test chart of Si tie layers. The results of fig. 10 show that both nano-modification and heat treatment can greatly improve the electron work function. The higher the electron work function, the higher the electron stability, the lower the activity, and the higher the resistance to electrical erosion and stress corrosion during use of the coating. Wherein the highest value of electron work function exists in 3% HfO 2 The heat treatment (1300 ℃ C., 2 h) of the modified Si bonding layer is 4.9eV of the environment barrier coating system, which is very close to a pure gold standard sample (the electronic work function value is 5.1 eV). The improvement of corrosion resistance of the environmental barrier coating system is an important reason for the great improvement of bonding strength.
Claims (10)
1. A method for improving the bonding strength of an environmental barrier coating by utilizing a nano modified silicon bonding layer is characterized by comprising the following steps of: the method for improving the bonding strength of the environmental barrier coating by utilizing the nano modified silicon bonding layer comprises the following steps:
step one, preparing modified Si powder by wet ball milling: mixing a modifier with Si powder to obtain mixed powder, ball-milling the mixed powder, adding a binder in the ball-milling process, ball-milling to obtain pug, drying, grinding and sieving the pug to obtain modified Si powder;
the modifier is nano HfO 2 Powder with the particle size of 80-100 nm;
the addition amount of the modifier is 1-3% of the mass of the Si powder;
the adhesive is polyvinyl alcohol (PVA), and the adhesive is 1.4-1.6% of the mass of the modifier;
step two, sequentially preparing a Si bonding layer, a mullite layer and Yb on the substrate by adopting plasma spraying 2 SiO 5 A layer to obtain an environmental barrier coating;
thirdly, performing heat treatment on the environmental barrier coating; the electron work function measurement value of the modified Si bonding layer in the environment barrier coating is 4.9eV;
the heat treatment process of the environmental barrier coating comprises the following steps: the heat treatment temperature is 900-1300 ℃, the heat treatment time is 1.8-2.2 h, and the heating rate is 4.8-5.2 ℃/min.
2. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: and step one, the particle size of the Si powder is 40-100 mu m.
3. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: the ball milling process comprises the following steps: the grinding ball selects ZrO 2 Ball, grinding ball diameter is 0.8~1.2mm, ball material volume ratio is 1: (3-5), wherein the ball milling rotating speed is 250-350 r/min, the ball milling time is 23-25 h, and the binder is added after 11-13 h in the ball milling process.
4. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: the screening is carried out by adopting a 150-200 mesh screen.
5. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: and step two, the matrix is a ceramic matrix composite material.
6. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: the plasma spraying process of the Si bonding layer in the second step is as follows: the spraying current is 450A, the spraying voltage is 45V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 10g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
7. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: the plasma spraying process of the mullite layer in the second step is as follows: the spraying current is 550A, the spraying voltage is 55V, the main air flow is 120, the carrier air flow is 60, the powder feeding speed is 8g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
8. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: yb in step two 2 SiO 5 The plasma spraying process of the layer comprises the following steps: the spraying current is 500A, the spraying voltage is 50V, the main air flow is 100, the carrier air flow is 50, the powder feeding speed is 6.3g/min, the powder feeding direction is 90 degrees, the spraying distance is 300mm, and the spraying speed is 30mm/s.
9. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: step one the HfO 2 The purity of the powder is 99.99%.
10. The method for improving the bonding strength of an environmental barrier coating by using a nano modified silicon bonding layer according to claim 1, wherein the method comprises the following steps: the heat treatment process of the environmental barrier coating comprises the following steps: the heat treatment temperature is 900-1300 ℃, the heat treatment time is 2 hours, and the heating rate is 5 ℃/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111662233.4A CN114293132B (en) | 2021-12-30 | 2021-12-30 | Method for improving bonding strength of environmental barrier coating by utilizing nano modified silicon bonding layer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111662233.4A CN114293132B (en) | 2021-12-30 | 2021-12-30 | Method for improving bonding strength of environmental barrier coating by utilizing nano modified silicon bonding layer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114293132A CN114293132A (en) | 2022-04-08 |
| CN114293132B true CN114293132B (en) | 2023-12-29 |
Family
ID=80974484
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111662233.4A Active CN114293132B (en) | 2021-12-30 | 2021-12-30 | Method for improving bonding strength of environmental barrier coating by utilizing nano modified silicon bonding layer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114293132B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115894081A (en) * | 2022-12-15 | 2023-04-04 | 西安交通大学 | Preparation method and material of high-melting-point and long-service-life environmental barrier coating bonding layer |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106435443A (en) * | 2016-09-30 | 2017-02-22 | 广东省新材料研究所 | Preparation method of environmental barrier coating layer |
| CN108715987A (en) * | 2018-06-29 | 2018-10-30 | 哈尔滨工业大学 | A method of improving thermal barrier coating bond strength |
| CN113264765A (en) * | 2021-06-25 | 2021-08-17 | 中国航发北京航空材料研究院 | HfO2-Si spray coating material and preparation method thereof |
| CN113278909A (en) * | 2021-05-25 | 2021-08-20 | 广东省科学院新材料研究所 | Thermal-environmental barrier coating and preparation method and application thereof |
-
2021
- 2021-12-30 CN CN202111662233.4A patent/CN114293132B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106435443A (en) * | 2016-09-30 | 2017-02-22 | 广东省新材料研究所 | Preparation method of environmental barrier coating layer |
| CN108715987A (en) * | 2018-06-29 | 2018-10-30 | 哈尔滨工业大学 | A method of improving thermal barrier coating bond strength |
| CN113278909A (en) * | 2021-05-25 | 2021-08-20 | 广东省科学院新材料研究所 | Thermal-environmental barrier coating and preparation method and application thereof |
| CN113264765A (en) * | 2021-06-25 | 2021-08-17 | 中国航发北京航空材料研究院 | HfO2-Si spray coating material and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 李归等.环境障涂层的新型Si-HfO2粘结层的制备.《中国稀土学会2021学术年会论文摘要集》.2021,摘要. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114293132A (en) | 2022-04-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7412019B2 (en) | Rare earth tantalate ceramics that prevent corrosion due to low melting point oxides and their manufacturing method | |
| CN111233446A (en) | Hafnium silicate environmental barrier coating for ceramic matrix composite material substrate and preparation method thereof | |
| EP1373684B1 (en) | Environmental and thermal barrier coating for ceramic components | |
| WO2008109214A2 (en) | Environmental barrier coating | |
| CN108911791B (en) | Environmental barrier coating and preparation method thereof | |
| CN107759251B (en) | Preparation method of high-toughness ceramic coating on surface of porous ceramic | |
| CN111534796B (en) | Nano mullite powder for plasma physical vapor deposition and preparation method thereof | |
| CN111960863B (en) | Ultrahigh-temperature corrosion-resistant composite material and preparation method thereof | |
| CN114293132B (en) | Method for improving bonding strength of environmental barrier coating by utilizing nano modified silicon bonding layer | |
| CN108424174B (en) | Multi-element complex phase nano boride, corresponding ultrahigh temperature oxidation resistant coating and preparation method | |
| CN111004990A (en) | MAX phase coating for thermal barrier coating anti-melting CMAS corrosion and thermal spraying preparation method | |
| CN111777413A (en) | Preparation method and application of nano gadolinium zirconate powder for plasma spraying | |
| CN109942294A (en) | A kind of rare earth samarium tantalate ceramics of different stoichiometric ratios and preparation method thereof of anti-low melting point oxide corrosion | |
| CN108950463A (en) | A kind of hot environment Barrier Coatings structure and preparation method thereof | |
| CN114920559A (en) | High-entropy oxide powder material for thermal barrier coating and preparation method and application thereof | |
| CN102674874A (en) | ZrC-SiC-LaB6 ternary superhigh temperature ceramic composite material and preparation method thereof | |
| CN110304946B (en) | Wide-temperature-range antioxidant coating on surface of ceramic matrix composite and preparation method thereof | |
| CN109678560A (en) | A kind of high temperature anti-ablation coating and its preparation method and application formed on basis material | |
| CN114853494A (en) | Composite ceramic powder with self-repairing capability and preparation method and application thereof | |
| CN111005024B (en) | Thermal barrier coating resistant to molten CMAS corrosion and preparation method thereof | |
| CN116444295B (en) | Slurry sintering preparation method of Si-based coating containing slow-release stabilizer | |
| CN114262216B (en) | Method for preparing environment barrier coating intermediate layer by utilizing TiC modified mullite | |
| CN111875416A (en) | Ceramic-based abradable seal material, coating, composite coating and preparation method | |
| CN109504932A (en) | A kind of preparation method of resistance to CMAS high temperature corrosion composite thermal barrier coating | |
| CN115386823B (en) | Environmental barrier coating capable of resisting high-temperature vapor corrosion and CMAS corrosion and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB03 | Change of inventor or designer information |
Inventor after: Deng Luwei Inventor after: Liu Saiyue Inventor after: Wang You Inventor after: Zhang Xiaodong Inventor before: Liu Saiyue Inventor before: Deng Luwei Inventor before: Wang You Inventor before: Zhang Xiaodong |
|
| CB03 | Change of inventor or designer information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |