CN105666956B - A kind of Y2O3/Al2O3Complex gradient hydrogen resistance coating and preparation method thereof - Google Patents
A kind of Y2O3/Al2O3Complex gradient hydrogen resistance coating and preparation method thereof Download PDFInfo
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Abstract
The present invention relates to a kind of Y2O3/Al2O3Complex gradient hydrogen resistance coating and preparation method thereof, the coating can be applied to the hydrogen infiltration-resistant of high-temperature vacuum heat-collecting tube.The Y2O3/Al2O3Complex gradient hydrogen resistance coating is by stainless steel tube and the Y for being applied to stainless steel pipe inner surface2O3/Al2O3Composite coating is formed.The composite coating is prepared by Metalorganic Chemical Vapor Deposition, and by repeated deposition aluminum oxide and yttria coating, it is about 0.1~20 μm of multilayer Y to obtain thickness2O3And Al2O3Complex gradient hydrogen resistance coating；The multilayer alternating structure that the coating is aluminum oxide by innermost layer and yittrium oxide outermost layer is forms.The hydrogen resistance coating and substrate combinating strength are high, preparation technology is simple and cost is cheap, and NdFeB permanent magnets improve more than 200 times.
Description
Technical field
The present invention relates to a kind of Y2O3/Al2O3Complex gradient hydrogen resistance coating and preparation method thereof, the coating can be applied to height
The hydrogen infiltration-resistant of warm vacuum heat collection pipe.
Background technology
The aging of heat transport fluid can produce free hydrogen in solar energy heat collection pipe, and hydrogen passes through mesotube by osmosis,
The vacuum annular space between mesotube and sleeve pipe is reached, causes the rise of annular space pressure, and then cause heat collecting pipe heat waste
The increase of mistake.The vacuum of annular gap between guarantee pipe, it is necessary to which taking appropriate measures reduces the amounts of hydrogen of vacuum annular space.It is early
Phase solves method including the use of gettering material, the finite capacity of gettering material is the drawbacks of this method, when the appearance of gettering material
When amount exhausts, the pressure of annular space can raise again.Therefore, can only temporarily be controlled by the way of absorption and can not be fundamentally
Solve the problems, such as, prevent hydrogen from permeating using hydrogen resistance coating therefore, researcher proposes, so as to efficient dominating set heat-tube vacuum annular
The pressure in space, reduce the thermal losses of thermal-collecting tube.
The hydrogen resistance coating occurred earliest, which is that CN1971168 is disclosed, uses Y2O3, can be significantly as resistance hydrogen material
The infiltration of hydrogen is prevented, makes absorption tube that there is less heat loss.But such resistance its thermal coefficient of expansion of hydrogen material and matrix exist compared with
Big mismatch, larger thermal stress is produced after certain thermal shock, between coating and matrix, causes coating to be separated with matrix, serious shadow
Ring coating NdFeB permanent magnets, for solve the above problems researcher find it is other be well combined with matrix, thermal coefficient of expansion is adapted to
Small hydrogen resistance coating is as transition zone.Al2O3Because its structure is more stable, can be formed particularly in preparation process α-
Al2O3, have very great help to coating performance, its insulation resistivity is higher, and NdFeB permanent magnets empirical tests are also relatively good, therefore, turns into
Most conventional material in hydrogen resistance coating.Because chemical gaseous phase depositing process high temperature prepares α-Al2O3When, it is easier to be formed big
Particle, bulky grain can often form brittlement phase, influence the reliability of coating, also influence the density and resistance hydrogen of coating material
Energy.
The content of the invention
In view of the foregoing, to overcome above-mentioned Y2O3、Al2O3The shortcomings that two kinds of coatings, the present invention are made using aluminum oxide coating layer
For tie coat, yttria coating prepares complex gradient hydrogen resistance coating, so as to improve NdFeB permanent magnets as hydrogen resistance coating, there is provided
It is a kind of with matrix is well combined, preparation technology is simple, cost is cheap MULTILAYER COMPOSITE gradient hydrogen resistance coating material.
A kind of multilayer Y2O3/Al2O3Complex gradient hydrogen resistance coating, the complex gradient hydrogen resistance coating is by stainless steel tube and application
In the Y of stainless steel pipe inner surface2O3/Al2O3Composite coating is formed.
Preferably, Y2O3/Al2O3Composite coating material is Y2O3And Al2O3；Y2O3/Al2O3Composite coating is Y2O3Coating and
Al2O3Coating alternating structure, total number of plies are more than or equal to 4 layers.
Y2O3/Al2O3The innermost layer of composite coating is Al2O3Coating, outermost layer Y2O3Coating.
Preferably, Y2O3/Al2O3The thickness of composite coating is between 0.1~20 μm.
Preferably, the stainless steel tube is austenitic stainless steel or martensitic stain less steel.
Y2O3Coating and Al2O3The thickness of coating can be mainly relevant with the preparation technology of each coating with identical or different；It is excellent
Choosing, multiple Y2O3The thickness of coating is identical or close, multiple Al2O3The thickness of coating is identical or close.
Present invention also offers above-mentioned Y2O3/Al2O3Application of the complex gradient hydrogen resistance coating in high-temperature vacuum heat-collecting tube,
I.e. above-mentioned stainless steel tube is the stainless steel mesotube of high-temperature vacuum heat-collecting tube；In the stainless steel mesotube of high-temperature vacuum heat-collecting tube
Inner surface applies Y2O3/Al2O3Composite coating.The high-temperature vacuum heat-collecting tube has spectral selective absorbing coating by outer wall
Stainless steel mesotube and glass outer sleeve pipe composition.
The present invention is difficult to preparation high-performance for current high-temperature vacuum heat-collecting tube inner surface, uniform and stable hydrogen resistance coating carries
A kind of fairly simple Y is supplied2O3And Al2O3Complex gradient hydrogen resistance coating and preparation method thereof, i.e., in high-temperature vacuum heat-collecting tube
Surface prepares Y using double evaporation source layerings first2O3-Al2O3MULTILAYER COMPOSITE gradient hydrogen resistance coating.
The present invention prepares Y using metal-organic chemical vapor deposition technology in high-temperature vacuum heat-collecting tube inner surface2O3-
Al2O3MULTILAYER COMPOSITE gradient hydrogen resistance coating, the complex gradient coating can effectively reduce H2In the permeability of stainless steel, so that very well
The purpose for reaching hydrogen infiltration-resistant.
A kind of Y2O3/Al2O3The preparation method of complex gradient hydrogen resistance coating, comprises the following steps：
(1) high-temperature vacuum heat-collecting tube stainless steel pipe inner surface is polished to 0.1~2 μm of roughness；
(2) Al is prepared in stainless steel pipe inner surface using metal-organic chemical vapor deposition technology2O3Coating；
(3) Y is prepared in stainless steel pipe inner surface using metal-organic chemical vapor deposition technology2O3Coating；
(4) repeat the above steps (2)；
(5) repeat the above steps (3)；
It is final to obtain the multilayer Y that thickness is about 0.1-20 μm2O3/Al2O3Complex gradient hydrogen resistance coating.
Prepare Al2O3Coating specific process parameter is：React 50-200 DEG C of source temperature；Carrier gas flux 40-500ml/min；Carry
Gas is hydrogen.
Prepare Y2O3Coating specific process parameter is：React 50-200 DEG C of source temperature；Carrier gas flux 10-300ml/min；Carry
Gas is hydrogen.
, will during mainly by current-carrying gas by the container in organometallic reaction source when the principle of the present invention is growth film
The saturated vapor of reaction source is brought into reaction chamber to be mixed with other reacting gas, and chemistry then occurs in heated thereon
The growth of film is facilitated in reaction.
The present invention compares with existing technological achievements, has advantages below and high-lighting achievement：First in high-temperature vacuum thermal-arrest
Inside pipe wall realizes the preparation of yittrium oxide and aluminum oxide mixing gradient hydrogen resistance coating, and the Y that this method is formed2O3And Al2O3It is compound
Gradient hydrogen resistance coating has the characteristics of thickness is controllable, and compactness is high, and the more uniform NdFeB permanent magnets of composition are excellent.
The Y of the present invention2O3/Al2O3Composite coating is prepared by metal-organic chemical vapor deposition method, passes through repeated deposition oxygen
Change aluminium and yttria coating, it is about 0.1~20 μm of multilayer Y to obtain thickness2O3And Al2O3Complex gradient hydrogen resistance coating；The coating by
The multilayer alternating structure composition that innermost layer is aluminum oxide and yittrium oxide outermost layer is.The hydrogen resistance coating can be used for stainless steel structure part
Hydrogen permeation barrier, particularly solar high-temperature vacuum heat-collecting tube inner tube stainless steel tube hydrogen permeation barrier.And the resistance hydrogen applies
Layer with substrate combinating strength is high, preparation technology is simple and cost is cheap, more than 200 times of NdFeB permanent magnets raising.
The invention will be further described in conjunction with the embodiments with reference to the accompanying drawings.
Brief description of the drawings
Fig. 1 is to scribble multilayer Y2O3/Al2O3The high-temperature vacuum heat-collecting tube structural representation of complex gradient hydrogen resistance coating.
Embodiment
As shown in figure 1, to scribble Y2O3/Al2O3The high-temperature vacuum heat-collecting tube structural representation of complex gradient hydrogen resistance coating,
It is from inside to outside yttria coating 1, aluminum oxide coating layer 2, yttria coating 1, aluminum oxide coating layer 2, stainless steel tube 3, heat absorbing coating
4th, vacuum area 5 and outer glass tube 6.Wherein, Y2O3/Al2O3Complex gradient hydrogen resistance coating by high-temperature vacuum heat-collecting tube stainless steel tube
3rd, aluminum oxide coating layer 2, yttria coating 1, aluminum oxide coating layer 2 and yttria coating 1 are combined.High-temperature vacuum heat-collecting tube is main
By outer wall there is the stainless steel mesotube of spectral selective absorbing coating and glass outer sleeve pipe to form, stainless steel tube and outer glass tube
Between form ring vaccum.Stainless steel tube is austenitic stainless steel or martensitic stain less steel.
Embodiment 1
Prepare the high-temperature vacuum heat-collecting tube Y that thickness is 0.5 μm2O3/Al2O3Complex gradient hydrogen resistance coating：
(1) stainless steel pipe inner surface is polished to 1 μm of roughness；
(2) Al is prepared in high-temperature vacuum heat-collecting tube inner surface using metal-organic chemical vapor deposition technology2O3Coating；Tool
Body technology parameter is：React 150 DEG C of source temperature；Reaction time 20min；Carrier gas flux 200ml/min.
(3) Y is prepared in high-temperature vacuum heat-collecting tube inner surface using metal-organic chemical vapor deposition technology2O3Coating；Tool
Body technology parameter is：React 100 DEG C of source temperature；Reaction time 20min；Carrier gas flux is 100ml/min.
(4) repeat the above steps (2)；
(5) repeat the above steps (3)；
It is final to obtain the multilayer Y that thickness is about 0.5 μm2O3And Al2O3Complex gradient hydrogen resistance coating.
Determine multilayer Y2O3And Al2O3H of the complex gradient hydrogen resistance coating at 400 DEG C2Permeability, NdFeB permanent magnets improve 200 times.
Embodiment 2
Prepare the high-temperature vacuum heat-collecting tube Y that thickness is 1 μm2O3/Al2O3Complex gradient hydrogen resistance coating：
(1) stainless steel pipe inner surface is polished to 0.5 μm of roughness；
(2) Al is prepared in high-temperature vacuum heat-collecting tube inner surface using metal-organic chemical vapor deposition technology2O3Coating；Tool
Body technology parameter is：React 180 DEG C of source temperature；Reaction time 50min；Carrier gas flux 200ml/min.
(3) Y is prepared in high-temperature vacuum heat-collecting tube inner surface using metal-organic chemical vapor deposition technology2O3Coating；Tool
Body technology parameter is：React 120 DEG C of source temperature；Reaction time 50min；Carrier gas flux 150ml/min.
(4) repeat the above steps (2)；
(5) repeat the above steps (3).
The multilayer Y that thickness is about 1 μm is obtained eventually2O3And Al2O3Complex gradient hydrogen resistance coating.
Determine multilayer Y2O3And Al2O3H of the complex gradient hydrogen resistance coating at 400 DEG C2Permeability, NdFeB permanent magnets improve 300 times.
Embodiment 3
Prepare the high-temperature vacuum heat-collecting tube Y that thickness is 0.8 μm2O3/Al2O3Complex gradient hydrogen resistance coating：
(1) stainless steel pipe inner surface is polished to 0.3 μm of roughness；
(2) Al is prepared in high-temperature vacuum heat-collecting tube inner surface using metal-organic chemical vapor deposition technology2O3Coating；Tool
Body technology parameter is：React 200 DEG C of source temperature；Reaction time 30min；Carrier gas flux 200ml/min.
(3) Y is prepared in high-temperature vacuum heat-collecting tube inner surface using metal-organic chemical vapor deposition technology2O3Coating；Tool
Body technology parameter is：React 160 DEG C of source temperature；Reaction time 30min；Carrier gas flux 80ml/min.
(4) repeat the above steps (2)；
(5) repeat the above steps (3).
It is final to obtain the multilayer Y that thickness is about 0.8 μm2O3And Al2O3Complex gradient hydrogen resistance coating.
Determine multilayer Y2O3And Al2O3H of the complex gradient hydrogen resistance coating at 400 DEG C2Permeability, NdFeB permanent magnets improve 460 times.
The multilayer Y of the present invention2O3And Al2O3Complex gradient hydrogen resistance coating can be used for the hydrogen permeation barrier of stainless steel structure part,
The particularly hydrogen permeation barrier of solar high-temperature vacuum heat-collecting tube inner tube stainless steel tube.And the hydrogen resistance coating is combined by force with matrix
Degree is high, and NdFeB permanent magnets improve more than 200 times.
Claims (7)
- A kind of 1. Y2O3/Al2O3Complex gradient hydrogen resistance coating, it is characterised in that：By stainless steel tube and it is applied to table in stainless steel tube The Y in face2O3/Al2O3Composite coating is formed, described Y2O3/Al2O3Composite coating is Y2O3Coating and Al2O3Coating alternating structure, Total number of plies is more than or equal to 4 layers, described Y2O3/Al2O3The innermost layer of composite coating is Al2O3Coating, outermost layer Y2O3Coating, Described Y2O3/Al2O3The thickness of composite coating is 0.1~20 μm.
- 2. Y according to claim 12O3/Al2O3Complex gradient hydrogen resistance coating, it is characterised in that：Described stainless steel tube is Austenitic stainless steel or martensitic stain less steel.
- 3. the Y described in claim 1 or 22O3/Al2O3Application of the complex gradient hydrogen resistance coating in high-temperature vacuum heat-collecting tube.
- 4. Y according to claim 32O3/Al2O3Application of the complex gradient hydrogen resistance coating in high-temperature vacuum heat-collecting tube, its It is characterised by：Apply Y in the inner surface of the stainless steel mesotube of high-temperature vacuum heat-collecting tube2O3/Al2O3Composite coating.
- 5. Y according to claim 42O3/Al2O3Application of the complex gradient hydrogen resistance coating in high-temperature vacuum heat-collecting tube, its It is characterised by：The high-temperature vacuum heat-collecting tube is had the stainless steel mesotube and outer layer glass of spectral selective absorbing coating by outer wall Glass sleeve pipe forms.
- A kind of 6. Y2O3/Al2O3The preparation method of complex gradient hydrogen resistance coating, comprises the following steps：(1) high-temperature vacuum heat-collecting tube stainless steel pipe inner surface is polished to 0.1~2 μm of roughness；(2) Al is prepared in stainless steel pipe inner surface using metal-organic chemical vapor deposition technology2O3Coating；(3) Y is prepared in stainless steel pipe inner surface using metal-organic chemical vapor deposition technology2O3Coating；(4) repeat the above steps (2)；(5) repeat the above steps (3)；It is final to obtain the multilayer Y that thickness is 0.1-20 μm2O3/Al2O3Complex gradient hydrogen resistance coating.
- 7. Y according to claim 62O3/Al2O3The preparation method of complex gradient hydrogen resistance coating, it is characterised in that：Prepare Al2O3The reaction source temperature of coating is 50-200 DEG C, carrier gas flux 40-500ml/min；Prepare Y2O3The reaction source temperature of coating Spend for 50-200 DEG C, carrier gas flux 10-300ml/min.
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| CN110218969A (en) * | 2019-07-16 | 2019-09-10 | 合肥工业大学 | A kind of preparation method of 316L stainless steel surface Y2O3 modified aluminide resistance tritium coating |
| CN110629179A (en) * | 2019-09-30 | 2019-12-31 | 武汉大学 | Novel nanometer multilayer structure composite tritium-resistant coating |
| CN113046695A (en) * | 2019-12-27 | 2021-06-29 | 有研工程技术研究院有限公司 | Yttrium/yttrium oxide composite hydrogen resistant coating |
| CN112410735B (en) * | 2020-09-29 | 2022-10-18 | 天津津航技术物理研究所 | Deliquescence-resistant Y 2 O 3 Base composite film structure and preparation method |
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Effective date of registration: 20190626 Address after: 101407 No. 11 Xingke East Street, Yanqi Economic Development Zone, Huairou District, Beijing Patentee after: Research Institute of engineering and Technology Co., Ltd. Address before: No. 2, Xinjie street, Xicheng District, Beijing, Beijing Patentee before: General Research Institute for Nonferrous Metals |