Design method of crystal / amorphous heterostructure hydrogen-resistant isotope coating
By constructing an amorphous coating on the crystal coating and introducing a crystal/amorphous heterogeneous interface, a "hydrogen isotope trap" is formed, which solves the problem of insufficient density of traditional coatings and achieves an efficient hydrogen isotope barrier effect.
Patent Information
- Application Number
- CN202510481235.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-17
- Publication Date
- 2025-08-01
AI Technical Summary
In the prior art, traditional pure-phase oxide tritium-retardant coatings have problems such as insufficient density and impurities introduction, resulting in the tritium permeability rate reduction factor (PRF) often below 103, which is difficult to meet the index requirements of 103 to 104 of China's fusion engineering experimental reactors.
Crystal coatings and amorphous coatings are prepared by wet chemistry. By constructing an amorphous coating on the crystal coating and introducing a crystal/amorphous heterogeneous interface between the two phase coatings, a "hydrogen isotope trap" is formed to improve the hydrogen resistance isotope performance of the coating.
The hydrogen resistance isotope performance of the coating has been greatly improved, and the permeability reduction factor (PRF) reaches more than 3,000, meeting the index requirements of China's fusion engineering experimental reactors.
Smart Images
Figure CN120400833A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of surface protection of engineering materials, especially the technology for suppressing hydrogen isotope permeation in hydrogen-containing environments such as nuclear energy and hydrogen energy. Specifically, it is a design method for a crystal / amorphous heterostructure hydrogen isotope barrier coating. Background Art
[0002] As a key fuel in nuclear energy systems, the atomic property of tritium with a small radius of ~53 pm leads to severe permeation and diffusion behavior in structural steel. Tritium leakage not only causes the loss of fusion fuel but also induces serious problems such as hydrogen embrittlement of structural steel and radioactive contamination. Currently, the most effective solution to solve the tritium leakage problem is to prepare an oxide coating with a low tritium permeability coefficient on the surface of structural steel, such as Cr2O3, ZrO2, Er2O3, Al2O3, and SiO2, etc. However, due to preparation process defects of traditional pure-phase oxide tritium barrier coatings, such as insufficient densification and impurity introduction, the Permeation Reduction Factor (PRF) is often lower than 10 3 , making it difficult to meet the index requirements of 10 3 ~10 4 put forward by the Chinese Fusion Engineering Experimental Reactor. Summary of the Invention
[0003] The purpose of the present invention is to provide a design method for a crystal / amorphous heterostructure tritium barrier coating. Based on the idea of introducing "hydrogen isotope traps", an amorphous coating is constructed on top of the crystal coating, and a crystal / amorphous heterointerface is introduced between the two-phase coatings, which serves as a "hydrogen isotope trap" to achieve the capture of hydrogen isotopes at the interface, thereby significantly improving the PRF (Permeation Reduction Factor, the larger the value, the better the hydrogen isotope barrier effect) of the coating.
[0004] To achieve the above purpose, the present invention adopts the following technical solutions:
[0005] A design method for a crystal / crystal heterostructure hydrogen isotope barrier coating, comprising:
[0006] 1) Prepare a crystal coating by a wet chemical method: Mix and stir 42.6 wt% - 91.8 wt% of ethanol, 3.3 wt% - 35.7 wt% of a metal source, and 3.8 wt% - 38.8 wt% of a co-solvent by mass percentage to obtain a first precursor sol. Coat the first precursor sol on a metal substrate through a spin coating process and perform a preheating treatment at 200°C - 500°C to obtain a crystal coating;
[0007] 2) Prepare the amorphous coating by the wet chemical method: Mix and stir 48.5 wt% - 93.4 wt% of water, 2.7 wt% - 31.0 wt% of aluminum source or silicon source, and 3.1 wt% - 33.7 wt% of cosolvent according to mass percentage to obtain the second precursor sol. After coating the second precursor sol on the crystal coating by the spin coating process, perform preheating treatment at 200 °C - 500 °C to obtain an amorphous coating on the crystal coating;
[0008] 3) Heat treatment of the crystal / amorphous heterostructure: Heat-treat the coating obtained in step 2), where the treatment temperature is higher than the crystallization temperature of the crystal layer and lower than the crystallization temperature of the amorphous layer, so that the crystal layer is fully crystallized and the amorphous layer remains amorphous.
[0009] Further, the thermal expansion coefficient of the crystal coating is similar to that of the metal substrate, which is 8 - 12×10 -6 / °C, and the crystallization temperature ≤ 500 °C.
[0010] Further, the crystallization temperature of the amorphous coating ≥ 800 °C.
[0011] Further, in step 1), the metal source is metal acetate or metal nitrate, where the metal is one of Cr, Zr, and Er.
[0012] Further, the crystal layer is a low-crystallization-temperature metal oxide, and the low-crystallization-temperature metal oxide is one of Cr2O3, ZrO2, and Er2O3.
[0013] Further, in step 4), the aluminum source is aluminum isopropoxide or aluminum nitrate, and the silicon source is tetraethoxysilane.
[0014] Further, the amorphous layer is a high-crystallization-temperature metal oxide, and the high-crystallization-temperature oxide is one of Al2O3 or SiO2.
[0015] Further, the rotation speed of the spin coating process in steps 1) and 2) is 2000 - 6000 rpm.
[0016] Further, the heat treatment temperature in step 3) is 500 - 800 °C.
[0017] A coating prepared by the above-described amorphous / crystalline heterostructure hydrogen isotope barrier coating design method.
[0018] The beneficial effects of the present invention are:
[0019] Through reasonable design of the crystal / amorphous coating heterostructure, a crystal / amorphous heterointerface was constructed, and "hydrogen traps" were formed at the interface, successfully achieving a significant improvement in the hydrogen isotope barrier performance of the coating. The performance of the two-phase composite coating is greater than the simple superposition of the performances of the two individual coatings, achieving the effect of "1 + 1 > 2" for the coating, and its PRF can reach more than 3000, meeting the index requirements of 10 3 ~10 4 required by China's Fusion Engineering Experimental Reactor. Brief Description of the Drawings
[0020] Figure 1 This is the cross-sectional structure (transmission electron microscope, TEM) of the crystal / amorphous (Cr2O3 / Al2O3) coating in the embodiment of the present invention and the deuterium distribution results of the coating after deuterium barrier testing (time-of-flight secondary ion mass spectrometry, TOF-SIMS);
[0021] Figure 2 This is the deuterium barrier performance result of the crystal / amorphous (ZrO2 / SiO2) coating in the embodiment of the present invention after deuterium barrier testing;
[0022] Figure 3 This is the deuterium barrier performance result of the crystal / amorphous (Er2O3 / Al2O3) coating in the embodiment of the present invention after deuterium barrier testing. Detailed Embodiments
[0023] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the drawings in the present invention.
[0024] Example 1:
[0025] 1) Selection of the crystal coating: Select Cr2O3 (9.6×10 -6 / °C) with a coefficient of thermal expansion close to that of the substrate (10 - 12×10 -6 / °C) and a crystallization temperature less than 500°C as the crystal layer.
[0026] 2) Preparation scheme of the crystal coating: Mix ethanol (67.8 wt%), chromium acetate (12.9 wt%) and a co-solvent (19.3 wt%) and stir to obtain a liquid-phase precursor sol. Cover the sol on the metal substrate through a spin-coating process to obtain a specimen. The spin-coating speed is 2000 rpm. After spin-coating, the specimen is preheated in a muffle furnace at 500°C.
[0027] 3) Selection of the amorphous coating: Select Al2O3 with a crystallization temperature greater than 800°C as the amorphous layer.
[0028] 4) Preparation scheme of amorphous coating: Mix water (76.0 wt%), aluminum isopropoxide (12.7 wt%) and co-solvent (11.3 wt%) and stir to obtain a liquid precursor sol. Cover the specimen obtained in 2) with the sol by spin coating process, and the spin coating speed is 4000 rpm. After spin coating, the specimen is preheated in a muffle furnace at 500 °C.
[0029] 5) Heat treatment parameters of crystal / amorphous heterostructure: The coating obtained in 4) is finally heat-treated at 650 °C for 2 h to make the crystal layer fully crystallize and the amorphous layer remain amorphous.
[0030] Example 2:
[0031] 1) Selection of crystal coating: Select ZrO2 (10.2×10 -6 / °C) with a coefficient of thermal expansion close to that of the substrate (10 - 12×10 -6 / °C) and a crystallization temperature less than 500 °C as the crystal layer.
[0032] 2) Preparation scheme of crystal coating: Mix ethanol (66.8 wt%), zirconium nitrate (16.9 wt%) and co-solvent (16.3 wt%) and stir to obtain a liquid precursor sol. Cover the metal substrate with the sol by spin coating process to obtain a specimen, and the spin coating speed is 4000 rpm. After spin coating, the specimen is preheated in a muffle furnace at 300 °C.
[0033] 3) Selection of amorphous coating: Select SiO2 with a crystallization temperature greater than 1000 °C as the amorphous layer.
[0034] 4) Preparation scheme of amorphous coating: Mix water (79.1 wt%), tetraethyl orthosilicate (15.8 wt%) and co-solvent (5.1 wt%) and stir to obtain a liquid precursor sol. Cover the specimen obtained in 2) with the sol by spin coating process, and the spin coating speed is 4000 rpm. After spin coating, the specimen is preheated in a muffle furnace at 300 °C.
[0035] 5) Heat treatment parameters of crystal / amorphous heterostructure: The coating obtained in 4) is finally heat-treated at 700 °C for 2.5 h to make the crystal layer fully crystallize and the amorphous layer remain amorphous, obtaining a ZrO2 / SiO2 coating.
[0036] Example 3:
[0037] 1) Selection of crystal coating: Select Er2O3 (8.2×10 -6 / °C) with a coefficient of thermal expansion close to that of the substrate (10 - 12×10 -6 / °C) and a crystallization temperature less than 500 °C as the crystal layer.
[0038] 2) Preparation scheme of the crystal coating: Ethanol (64.2 wt%), erbium acetate (16.3 wt%), and a co-solvent (19.5 wt%) are mixed and stirred to obtain a liquid-phase precursor sol. The sol is coated on a metal substrate through a spin-coating process to obtain a sample. The spin-coating speed is 6000 rpm. After spin-coating, the sample is pre-heat-treated in a muffle furnace at 200 °C.
[0039] 3) Selection of the amorphous coating: Al2O3 with a crystallization temperature greater than 800 °C is selected as the amorphous layer.
[0040] 4) Preparation scheme of the amorphous coating: Water (72.5 wt%), aluminum isopropoxide (14.5 wt%), and a co-solvent (13.0 wt%) are stirred and mixed to obtain a liquid-phase precursor sol. The sol is coated on the sample obtained in 2) through a spin-coating process. The spin-coating speed is 4000 rpm. After spin-coating, the sample is pre-heat-treated in a muffle furnace at 200 °C.
[0041] 5) Heat treatment parameters of the crystal / amorphous heterostructure: The coating obtained in 4) is finally heat-treated at 800 °C for 1 h, so that the crystal layer is fully crystallized and the amorphous layer remains amorphous, obtaining an Er2O3 / Al2O3 coating.
[0042] Figure 1 Figure shows the cross-sectional structure (transmission electron microscope, TEM) of the crystal / amorphous (Cr2O3 / Al2O3) coating in Example 1 and the deuterium distribution results of the coating after the deuterium retention test (time-of-flight secondary ion mass spectrometry, TOF-SIMS). From the FFT results in the TEM, it can be seen that the Cr2O3 under the coating is the crystal layer and the surface Al2O3 layer is the amorphous layer. The deuterium distribution results of the coating after the deuterium retention test are obtained by TOF-SIMS. As can be seen from the figure, after the deuterium retention test, deuterium mainly accumulates at the interface between Cr2O3 and Al2O3, and its concentration is 198% of the diffusion source. Its abnormal diffusion behavior is due to the "trapping effect" of the crystal / amorphous heterointerface, making it difficult for hydrogen isotopes to diffuse at the interface, resulting in an increase in concentration.
[0043] Figure 2 Figure shows the deuterium retention test results of the crystal / amorphous (ZrO2 / SiO2) coating in Example 2. The deuterium permeation flux of the pure ZrO2 coating is 2.8×10 -8 mol m -2 s -1 、the deuterium permeation flux of the SiO2 coating is 4.2×10 -9 mol m -2 s -1 ,and the deuterium permeation flux of the crystal / amorphous (ZrO2 / SiO2) coating is 3.0×10 -11 mol m -2 s -1, the corresponding PRFs are 16, 112, and 1567 respectively. The PRF of the composite coating is increased by about 11 times compared to the sum of the PRFs of the two pure-phase coatings.
[0044] Figure 3 For the deuterium resistance test results of the crystal / amorphous (Er2O3 / Al2O3) coating in Example 3, at 500 °C, the deuterium permeation flux of the pure Er2O3 coating is 7.7×10 -10 mol m -2 s -1 , the deuterium permeation flux of the Al2O3 coating is 5.8×10 -9 mol m -2 s -1 , and the deuterium permeation flux of the crystal / amorphous (Er2O3 / Al2O3) coating is 1.5×10 -10 mol m -2 s -1 , the corresponding PRFs are 610, 81, and 3133 respectively. The PRF of the composite coating is increased by about 3.5 times compared to the sum of the PRFs of the two pure-phase coatings.
[0045] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
Claims
1. A method for designing a hydrogen isotope barrier coating of a crystal / crystal heterostructure, characterized in that Including: 1) Preparing a crystal coating by a wet chemical method: Mixing 42.6 wt% - 91.8 wt% of ethanol, 3.3 wt% - 35.7 wt% of a metal source, and 3.8 wt% - 38.8 wt% of a co-solvent by mass percentage and stirring to obtain a first precursor sol, coating the first precursor sol on a metal substrate through a spin coating process, and performing a preheating treatment at 200°C - 500°C to obtain a crystal coating; 2) Preparing an amorphous coating by a wet chemical method: Mixing 48.5 wt% - 93.4 wt% of water, 2.7 wt% - 31.0 wt% of an aluminum source or a silicon source, and 3.1 wt% - 33.7 wt% of a co-solvent by mass percentage and stirring to obtain a second precursor sol, coating the second precursor sol on the crystal coating through a spin coating process, and performing a preheating treatment at 200°C - 500°C to obtain an amorphous coating on the crystal coating; 3) Heat treatment of the crystal / amorphous heterostructure: Performing heat treatment on the coating obtained in step 2), where the treatment temperature is higher than the crystallization temperature of the crystal layer and lower than the crystallization temperature of the amorphous layer, so that the crystal layer is fully crystallized and the amorphous layer remains amorphous.
2. The design method of the amorphous / crystalline heterostructure hydrogen isotope barrier coating according to claim 1, wherein The thermal expansion coefficient of the crystal coating is similar to that of the metal substrate, which is 8-12×10 -6 / °C, and the crystallization temperature is ≤500 °C.
3. The design method of the amorphous / crystalline heterostructure hydrogen isotope barrier coating according to claim 1, characterized in that, The crystallization temperature of the amorphous coating ≥ 800°C.
4. The method for designing an amorphous / crystalline heterostructure hydrogen isotope barrier coating according to claim 1, wherein In step 1), the metal source is a metal acetate or a metal nitrate, and the metal is one of Cr, Zr, and Er.
5. The design method of the amorphous / crystalline heterostructure hydrogen isotope barrier coating according to claim 4, wherein The crystal layer is a low-crystallization-temperature metal oxide, and the low-crystallization-temperature metal oxide is one of Cr2O3, ZrO2, and Er2O3.
6. The design method of the amorphous / crystalline heterostructure hydrogen isotope barrier coating according to claim 1, wherein In step 4), the aluminum source is aluminum isopropoxide or aluminum nitrate, and the silicon source is tetraethoxysilane.
7. The design method of the amorphous / crystalline heterostructure hydrogen isotope barrier coating according to claim 6, characterized in that, The amorphous layer is a high-crystallization-temperature metal oxide, and the high-crystallization-temperature oxide is one of Al2O3 or SiO2.
8. The design method of the amorphous / crystalline heterostructure hydrogen isotope barrier coating according to claim 1, wherein The rotation speed of the spin coating process in steps 1) and 2) is 2000 - 6000 rpm.
9. The method for designing an amorphous / crystalline heterojunction hydrogen isotope coating according to claim 1, wherein The heat treatment temperature in step 3) is 500 - 800°C.
10. A coating prepared by the amorphous / crystal heterostructure hydrogen isotope barrier coating design method according to any one of claims 1 - 9.