Alloy oxide tritium-resistant coating and preparation method thereof

Abstract

The invention belongs to the technical field of new materials, and discloses an alloy oxide tritium-resistant coating and a preparation method thereof. The preparation method comprises the following steps: after a metal base material is pretreated, sputtering a metal Cr target by adopting a magnetron sputtering technology, and depositing a pure Cr base layer on the surface of the metal base material; a magnetron sputtering technology is adopted, an oxidation transition layer and an alloy oxide layer are sequentially deposited on the surface of a pure Cr base layer by sputtering an Al target and a Cr target at the same time in a dual-power mode, and a composite coating is obtained; and the composite coating is subjected to annealing treatment, and the alloy oxide tritium-resistant coating containing the crystalline oxide is obtained. According to the preparation method, the problem of thermal mismatch between the coating and the base material can be effectively relieved, and the alloy oxide tritium-resistant coating with high binding force with the base material is successfully formed on the surface of the metal base material; the preparation method is simple in technological process, free of pollution in the whole process, high in deposition speed and capable of saving cost; and the prepared alloy oxide tritium-resistant coating has good tritium-resistant and hydrogen-resistant performance.

Description

Technical Field

[0001] The present invention relates to the technical field of new materials, and in particular to an alloy oxide tritium barrier coating and a preparation method thereof. Background Art

[0002] Controlled nuclear fusion is an ideal clean energy source, which has attracted much attention due to its advantages in fuel reserves and minimal damage to the environment. However, in the tritium loop of the fusion reactor, due to the small atomic number of tritium, tritium can easily penetrate and diffuse into the metal material structure, which will not only deteriorate the material performance, cause hydrogen embrittlement and corrosion failure of the material, cause radioactive pollution and economic losses, but also have great safety hazards. For example, it may cause leakage and penetration of the tritium loop during the operation of the fusion reactor, thereby causing safety problems of nuclear leakage. Coating a tritium barrier coating on the surface of tritium-related materials is an effective solution to prevent tritium leakage and tritium penetration in tritium-related materials. Metal oxides have become a hot spot in the research of tritium barrier coatings due to their stable chemical properties and good tritium barrier properties.

[0003] Among the commonly used oxide materials, aluminum oxide has attracted widespread attention due to its excellent tritium barrier properties, high hardness and excellent thermodynamic properties. However, aluminum oxide has a variety of phase structures, among which α-aluminum oxide has the best high-temperature chemical stability and tritium barrier properties, and the tritium barrier factor can reach up to 10,000. The main preparation methods used in the prior art for preparing metal oxide coatings are chemical vapor deposition and magnetron sputtering deposition. However, when chemical vapor deposition is used to prepare α-aluminum oxide, since the phase formation temperature of α-aluminum oxide is as high as 1200°C, the matrix material used to transport tritium, such as stainless steel pipes, can hardly withstand such high temperatures, resulting in the loss of matrix performance and deformation of the matrix during the actual preparation process, and it is difficult to effectively form a tritium barrier coating on the surface of the matrix material for transporting tritium. When α-alumina is prepared by magnetron sputtering deposition, low-temperature deposition results in the coating being unable to form an α-alumina phase. The actual deposited alumina is usually formed as an amorphous film, and the tritium barrier factor of amorphous alumina can be sharply reduced to below 50.

[0004] Based on the above, it can be known that the above-mentioned several prior art preparation methods are difficult to achieve effective formation of tritium-blocking coatings on the base material that transports tritium. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an alloy oxide tritium barrier coating and a preparation method thereof. The present invention uses magnetron sputtering technology to prepare an alloy oxide coating on the surface of stainless steel, and adopts a medium frequency / DC pulse dual power supply mode combined with a metal aluminum target and a metal chromium target for reactive co-sputtering, which can effectively inhibit target surface poisoning, and at the same time, by regulating the target power, the ratio of Al and Cr elements in the coating can be adjusted. The metal base layer and the gradient oxidation transition layer in the coating act together as an intermediate transition layer, which can reduce the thermal mismatch effect between the coating and the substrate and improve the film-substrate interface bonding; the annealing treatment can effectively promote the transformation of the oxide from an amorphous state to a crystalline state, and improve the tritium barrier performance of the coating.

[0006] The alloy oxide tritium barrier coating and the preparation method thereof of the present invention are realized by the following technical scheme:

[0007] The present invention provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0008] Step 1: After polishing and cleaning the metal substrate, glow sputtering cleaning is performed to obtain a clean metal substrate.

[0009] Step 2: In an argon atmosphere, a magnetron sputtering technique is used to deposit a layer of pure Cr primer on the surface of a clean metal substrate by sputtering a metal Cr target.

[0010] Step 3, using magnetron sputtering technology, sequentially depositing an oxide transition layer and an alloy oxide layer:

[0011] Argon and oxygen are introduced, and magnetron sputtering technology is used. In a dual power supply mode, an Al target and a Cr target are sputtered simultaneously, and the oxygen flux is gradually increased to a stable flow within 5 minutes after the start of sputtering, so as to form a gradient-distributed oxidation transition layer on the surface of the pure Cr base layer; then, the flow ratio of argon to oxygen is maintained and the Al target and the Cr target are continued to be sputtered simultaneously to deposit an alloy oxide layer on the surface of the oxidation transition layer, so as to form a composite coating of a pure Cr base layer, an oxidation transition layer and an alloy oxide layer from the inside to the outside on the surface of the metal substrate.

[0012] Step 4: annealing the composite coating to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides.

[0013] It should be noted that in the above step 1, the present invention does not limit the specific material of the metal substrate, and the corresponding metal substrate can be selected according to actual needs. For example, in some preferred embodiments of the present invention, the material of the metal substrate used includes but is not limited to any one of austenitic stainless steel, low-activity martensitic stainless steel, heat-resistant steel, and high-temperature alloy.

[0014] In order to improve the bonding strength between the substrate and the coating, the present invention first polishes the metal substrate to remove impurities and defects on the surface of the metal substrate, and then cleans and removes impurities remaining during polishing. In some preferred embodiments of the present invention, the surface is polished to a surface roughness R a <0.2 μm, it is considered that the impurities and defects on the surface of the metal substrate are completely removed. The present invention does not specifically limit the cleaning operation after polishing, and the cleaning can be performed according to the conventional cleaning operation in the art.

[0015] It can be understood that since the glow sputtering cleaning process and the magnetron sputtering process using magnetron sputtering technology are both carried out in a magnetron sputtering device, the present invention first installs the polished and cleaned metal substrate on the working turntable in the vacuum chamber of the magnetron sputtering device, and places the various target materials required for deposition on the target position in the magnetron sputtering vacuum chamber, and then performs the glow sputtering cleaning process and subsequent magnetron sputtering in sequence.

[0016] In order to facilitate the glow sputtering cleaning process and the subsequent magnetron sputtering, the present invention places the metal Al target and the Cr target on the target position in the magnetron sputtering vacuum chamber respectively, and connects the Al target to the medium frequency power supply, and the Cr target to the DC pulse power supply, so as to ensure that in the subsequent magnetron sputtering process, a layer of pure Cr primer layer is first deposited on the surface of the clean metal substrate by sputtering the metal Cr target. Then, in the dual power mode, by sputtering the Al target and the Cr target at the same time, an oxidation transition layer and an alloy oxide layer are sequentially deposited on the surface of the pure Cr primer layer.

[0017] The present invention performs glow sputtering cleaning on the surface of the metal substrate after polishing and cleaning to further remove impurities such as oil, dust, oxides, rust, welding slag and sweat stains on the surface of the metal substrate, thereby facilitating the improvement of the bonding strength between the subsequently deposited coating and the substrate.

[0018] In some preferred embodiments of the present invention, when performing glow sputtering cleaning treatment, the vacuum chamber of the magnetron sputtering equipment is first evacuated to <0.005Pa, and then argon gas is introduced into the vacuum chamber of the magnetron sputtering equipment to a pressure of 0.4Pa~2.0Pa. A bipolar pulse power supply is used, and the bias voltage applied to the substrate is -200V~1000V, and the treatment is performed for at least 5 minutes.

[0019] In the above step 2, the present invention first uses magnetron sputtering technology in an argon atmosphere to deposit a layer of pure Cr primer on the surface of a clean metal substrate by sputtering a metal Cr target, so as to reduce the thermal mismatch effect between the coating and the substrate through the pure Cr primer, thereby improving the film-substrate interface bonding.

[0020] In some preferred embodiments of the present invention, when depositing the pure Cr coating layer, the gas pressure is 0.2Pa~1.6Pa, the bias voltage applied to the substrate is -30V~300V, and the sputtering time is 5min~15min, so as to deposit a layer of pure Cr coating layer with a thickness of 50nm~200nm on the surface of the metal substrate, thereby reducing the thermal mismatch effect between the coating and the substrate through the pure Cr coating layer of this thickness, thereby improving the film-substrate interface bonding.

[0021] In order to solve the defect that the coating deposited by low-temperature magnetron sputtering is difficult to effectively achieve the tritium blocking effect, the present invention takes into account that the tritium blocking factor of chromium oxide is as high as 100 to 3000, and chromium oxide and α-alumina have the same close-packed hexagonal structure (i.e., hcp crystal structure), and the lattice parameters between the two are very close. Moreover, the crystallization temperature of chromium oxide is relatively low, and the crystal structure can be obtained at 450°C, which is easy to prepare by magnetron sputtering. Therefore, the present invention proposes to use Al target and Cr target as sputtering target materials, and utilize the characteristics that chromium oxide is easy to prepare and is extremely close to the lattice parameter of α-alumina. By sputtering Al target and Cr target at the same time, the chromium oxide formed by sputtering Cr target has an induction effect on α-alumina crystals, which promotes Al target sputtering to form α-alumina, and then forms a tritium blocking coating composed of chromium oxide and α-alumina on the surface of pure Cr base layer.

[0022] In the above step 3, the present invention forms a tritium barrier coating composed of chromium oxide and α-aluminum oxide on the surface of the metal substrate by sequentially depositing an oxide transition layer and an alloy oxide layer on the surface of the pure Cr base layer, and further improves the film-base interface bonding strength. In some preferred embodiments of the present invention, the oxide transition layer and the alloy oxide layer are sequentially deposited on the surface of the pure Cr base layer by the following steps:

[0023] 3.1) Deposition of oxide transition layer:

[0024] Argon and oxygen are introduced into the vacuum chamber of the magnetron sputtering equipment. Magnetron sputtering technology is used. In the dual power supply mode of medium frequency power supply and DC pulse power supply, Al target and Cr target are sputtered simultaneously. The argon flux is kept constant during sputtering, and the oxygen flux is gradually increased to a stable flow rate within 5 minutes after the start of sputtering. During the magnetron sputtering process, the argon flux is constant and the oxygen content is gradually increased, so that an oxide transition layer with a gradient oxygen content can be deposited on the surface of the pure Cr base layer.

[0025] The present invention forms a gradient-distributed oxidation transition layer on the pure Cr base layer, which can not only avoid the situation that the metal of the pure Cr base layer is converted into metal oxide due to the pure Cr base layer being exposed to too much oxygen, thereby causing a thermal mismatch effect between the coating and the substrate; moreover, the gradient-distributed oxidation transition layer and the pure Cr base layer can work synergistically and serve as an intermediate transition layer between the metal substrate and the alloy oxide layer. The components of the intermediate transition layer are distributed in a gradient, which can effectively improve the bonding ability between different coatings, thereby further improving the film-base interface bonding force, and effectively reducing the problem of coating shedding caused by the thermal mismatch effect between the coating and the substrate.

[0026] 3.2) Deposition of alloy oxide layer:

[0027] The present invention simultaneously sputters Al targets and Cr targets by maintaining the oxygen flux at a stable flow rate, that is, maintaining a stable flow ratio of argon to oxygen, so as to further deposit a layer of alloy oxide layer with uniform components and dense structure on the surface of the gradient-distributed oxidation transition layer, that is, forming a composite coating of pure Cr primer layer, oxidation transition layer and alloy oxide layer from inside to outside on the surface of the metal substrate, that is, forming a gradient distribution of thermal expansion coefficient on the surface of the metal substrate, thereby effectively improving the membrane-substrate interface bonding strength.

[0028] In the above 3.1), when preparing the oxidation transition layer, the present invention can not only achieve a gradient distribution of the oxidation transition layer components by gradually increasing oxygen, but also effectively inhibit the occurrence of poisoning on the surface of the target material. In some preferred embodiments of the present invention, when the oxygen flux reaches a stable flow rate, the flow ratio of argon to oxygen is 3 to 7:1.

[0029] In some preferred embodiments of the present invention, when depositing the oxide transition layer and the alloy oxide layer, the gas pressure is 0.1Pa~1Pa, and the bias voltage applied to the substrate is -30V~200V, so as to achieve uniform distribution of aluminum oxide and chromium oxide and improve the bonding strength between the aluminum oxide and chromium oxide and the underlying substrate and coating.

[0030] When depositing the alloy oxide layer, the deposition duration can be adjusted accordingly according to the actual required thickness of the alloy oxide layer. For example, in some preferred embodiments of the present invention, when it is necessary to prepare an alloy oxide layer with a thickness of 0.1 μm to 2 μm, the deposition time is 10 min to 600 min.

[0031] In some preferred embodiments of the present invention, when depositing the oxide transition layer and the alloy oxide layer, the total target sputtering power of the Al target and the Cr target is 100W to 5000W. According to the process requirements, the corresponding power ratio of the Al target and the Cr target can be selected for sputtering. For example, in some more preferred embodiments of the present invention, the atomic ratio of the Al element to the Cr element in the formed alloy oxide tritium barrier coating is adjusted by adjusting the power ratio of the Al target and the Cr target.

[0032] The present invention also performs an annealing treatment on the composite coating formed by magnetron sputtering, so as to promote the transformation of the oxide from an amorphous state to a crystalline state through annealing treatment, such as transforming amorphous chromium oxide into crystalline chromium oxide, thereby improving the tritium barrier performance of the coating. In some preferred embodiments of the present invention, the annealing temperature of the annealing treatment is 200°C to 800°C, and the annealing holding time is 10min to 360min.

[0033] The present invention also provides an alloy oxide tritium barrier coating prepared by the above preparation method, in which the atomic ratio of Al element to Cr element is 1-2:1-9.

[0034] It should be noted that the alloy oxide tritium barrier coating prepared by the above method of the present invention comprises a pure Cr base layer, an oxidized transition layer and an alloy oxide layer from the substrate surface to the outside, and has a composite structure with a gradient distribution. The pure Cr base layer and the gradient-distributed oxidized transition layer can reduce the thermal mismatch effect between the coating and the substrate, thereby improving the film-substrate interface bonding, and has a dense structure and does not contain hydrogen elements, which can avoid the adverse effects of hydrogen embrittlement on the substrate. The alloy oxide layer on the surface contains crystalline metal oxides, which can effectively improve the tritium and hydrogen barrier properties of the substrate.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The present invention performs glow sputtering cleaning treatment after polishing and cleaning the metal substrate to achieve cleaning of the metal substrate. Then, a layer of pure Cr primer layer is deposited on the surface of the cleaned metal substrate by using magnetron sputtering technology. Then, by using magnetron sputtering technology, in a dual power supply mode of a medium frequency power supply and a direct current pulse power supply, an Al target and a Cr target are reactively co-sputtered, the argon flux is kept constant during sputtering, and the oxygen flux is gradually increased to a stable flow rate within 5 minutes after the start of sputtering. Since the oxygen content is gradually increased during the magnetron sputtering process, a layer of oxidized transition layer with a gradient distribution of oxygen content can be deposited on the surface of the pure Cr primer layer, and then the thermal mismatch effect between the coating and the substrate is further reduced through the synergistic effect of the gradient distributed oxidized transition layer and the pure Cr primer layer, thereby further improving the film-substrate interface bonding force. Then, the present invention simultaneously sputters the Al target and the Cr target by keeping the oxygen flux at a stable flow rate, that is, keeping the argon gas and the oxygen at a stable flow rate ratio, so as to further deposit and form an alloy oxide layer with uniform components and dense structure on the surface of the gradient-distributed oxidation transition layer, and then form a composite coating of pure Cr primer layer, oxidation transition layer and alloy oxide layer from inside to outside on the surface of the metal substrate. Then, the composite coating is annealed to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, so as to obtain an alloy oxide tritium barrier coating with crystalline oxide.

[0037] The preparation method of the present invention successfully realizes the preparation of the alloy oxide tritium barrier coating on the surface of the metal substrate, solving the thermal mismatch problem between the tritium barrier coating based on aluminum oxide and the metal substrate in the prior art. In addition, the alloy oxide tritium barrier coating of the present invention has a strong bonding force with the metal substrate, effectively improving the tritium and hydrogen barrier properties of the metal substrate. In addition, the preparation method of the present invention is simple, pollution-free throughout the process, has a fast deposition speed, and saves costs.

[0038] The preparation method of the invention is applicable to nonferrous metals such as austenitic stainless steel, low-activity martensitic stainless steel, heat-resistant steel, and high-temperature alloys.

[0039] The present invention adopts a medium frequency / DC pulse dual power supply mode combined with a metal aluminum target and a metal chromium target for reactive co-sputtering, which can effectively inhibit target surface poisoning. At the same time, by regulating the target power, the ratio of Al and Cr elements in the coating can be adjusted, and a specific composition with an Al / Cr atomic ratio between 2:1 and 1:9 can be prepared.

[0040] The alloy oxide tritium barrier coating prepared by the present invention comprises a pure Cr base layer, an oxidized transition layer and an alloy oxide layer in order from the substrate surface to the outside, and has a composite structure with a gradient distribution, wherein the pure Cr base layer and the gradient-distributed oxidized transition layer can reduce the thermal mismatch effect between the coating and the substrate, thereby improving the film-substrate interface bonding, and has a dense structure and does not contain hydrogen elements, thereby avoiding the adverse effects of hydrogen embrittlement on the substrate, and the alloy oxide layer on the surface contains crystalline metal oxides, which can effectively improve the tritium and hydrogen barrier properties of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a surface scanning electron microscope image of the coating of Comparative Example 1.

[0042] Figure 2 This is a cross-sectional scanning electron microscope image of the coating of Comparative Example 1.

[0043] Figure 3 This is a surface scanning electron microscope image of the coating of Comparative Example 2.

[0044] Figure 4 Surface scanning electron microscope image of the coating of Example 1.

[0045] Figure 5 Surface scanning electron microscope image of the coating of Example 2.

[0046] Figure 6 Surface scanning electron microscope image of the coating of Example 3.

[0047] Figure 7 This is the XRD spectrum of the coating on the surface of Example 1. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present invention will be described clearly and completely below.

[0049] Example 1

[0050] This embodiment provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0051] Step 1: After polishing and cleaning the metal substrate, perform glow sputtering cleaning to obtain a clean metal substrate:

[0052] 1.1) In this embodiment, a 316L stainless steel substrate is used as a metal substrate, which is polished and cleaned to obtain a polished 316L stainless steel substrate.

[0053] 1.2) The polished metal substrate is dried and mounted on a workpiece turntable of a magnetron sputtering vacuum chamber, and two metal Al targets and one metal chromium target are placed on target positions in the magnetron sputtering vacuum chamber, respectively. The metal Al target is connected to a medium frequency power supply, and the metal Cr target is connected to a DC pulse power supply.

[0054] 1.3) Evacuate the vacuum chamber of the magnetron sputtering equipment to 5×10 -3 Pa, and then argon gas was introduced to control the gas pressure to 0.5 Pa. The bias voltage applied to the substrate was -800 V, and the substrate was cleaned by glow sputtering for 10 minutes to obtain a clean metal substrate.

[0055] Step 2: In an argon atmosphere, a layer of pure Cr primer is deposited on the surface of a clean metal substrate by sputtering a metal Cr target using magnetron sputtering technology:

[0056] Argon gas was introduced into the vacuum chamber, the Cr target was turned on, the working gas pressure was controlled to be 0.6 Pa, the bias voltage applied to the substrate was -150 V, the sputtering time was 10 min, and a layer of pure Cr primer was deposited on the surface of the clean metal substrate.

[0057] Step 3, using magnetron sputtering technology, sequentially depositing an oxide transition layer and an alloy oxide layer:

[0058] 3.1) Deposition of oxide transition layer:

[0059] By introducing argon and oxygen into the vacuum chamber of the magnetron sputtering equipment, using magnetron sputtering technology, in the dual power supply mode of medium frequency power supply and DC pulse power supply, controlling the working gas pressure to 0.6Pa, applying a bias voltage of -200V to the substrate, turning on the metal Al target and the metal Cr target, adjusting the total power to 4000W, and the power ratio of the metal Al target to the metal Cr target to 3:1, by sputtering the Al target and the Cr target at the same time, keeping the argon flux constant during sputtering, and gradually increasing the oxygen flux to an argon-oxygen partial pressure ratio of 3:1 within 5 minutes after the start of sputtering, a layer of oxide transition layer with a gradient oxygen content is deposited on the surface of the pure Cr base layer.

[0060] 3.2) Deposition of alloy oxide layer:

[0061] The argon-oxygen partial pressure ratio was maintained at 3:1, and the Al target and the Cr target were sputtered simultaneously under the above-mentioned magnetron sputtering conditions for 180 min to further deposit an alloy oxide layer on the surface of the gradient-distributed oxide transition layer to obtain a composite coating consisting of a pure Cr base layer, an oxide transition layer and an alloy oxide layer from the inside to the outside.

[0062] 3.3) After coating, stop ventilation and maintain vacuum until the substrate temperature is ≤60℃.

[0063] Step 4, annealing the composite coating to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides:

[0064] The annealing atmosphere is air, the heating rate is 5°C / min, the annealing temperature is 600°C, the holding time is 2h, and then the furnace is cooled to room temperature.

[0065] After testing, the thickness of the alloy oxide tritium barrier coating obtained in this embodiment is 2.98 μm. In addition, among the metal element components of the alloy oxide tritium barrier coating in this embodiment, the atomic percentage of aluminum is 60.7%, and the atomic percentage of chromium is 29.3%.

[0066] Example 2

[0067] This embodiment provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0068] Step 1: After polishing and cleaning the metal substrate, perform glow sputtering cleaning to obtain a clean metal substrate:

[0069] 1.1) In this embodiment, a 316L stainless steel substrate is used as a metal substrate, which is polished and cleaned to obtain a polished 316L stainless steel substrate.

[0070] 1.2) The polished metal substrate is dried and mounted on a workpiece turntable of a magnetron sputtering vacuum chamber, and two metal Al targets and one metal chromium target are placed on target positions in the magnetron sputtering vacuum chamber, respectively. The metal Al target is connected to a medium frequency power supply, and the metal Cr target is connected to a DC pulse power supply.

[0071] 1.3) Evacuate the vacuum chamber of the magnetron sputtering equipment to 5×10 -3 Pa, and then argon gas was introduced to control the gas pressure to 0.5 Pa. The bias voltage applied to the substrate was -800 V, and the substrate was cleaned by glow sputtering for 10 minutes to obtain a clean metal substrate.

[0072] Step 2: In an argon atmosphere, a layer of pure Cr primer is deposited on the surface of a clean metal substrate by sputtering a metal Cr target using magnetron sputtering technology:

[0073] Argon gas was introduced into the vacuum chamber, the Cr target was turned on, the working gas pressure was controlled to be 0.6 Pa, the bias voltage applied to the substrate was -150 V, the sputtering time was 10 min, and a layer of pure Cr primer was deposited on the surface of the clean metal substrate.

[0074] Step 3, using magnetron sputtering technology, sequentially depositing an oxide transition layer and an alloy oxide layer:

[0075] 3.1) By introducing argon and oxygen into the vacuum chamber of the magnetron sputtering equipment, the magnetron sputtering technology is adopted. In the dual power supply mode of the medium frequency power supply and the DC pulse power supply, the working gas pressure is controlled to be 0.6 Pa, the bias voltage applied to the substrate is -200 V, the metal Al target and the metal Cr target are turned on, the total power is adjusted to 4000 W, and the power ratio of the metal Al target to the metal Cr target is 1:3. By sputtering the Al target and the Cr target at the same time, the argon flux is kept constant during sputtering, and the oxygen flux is gradually increased to an argon-oxygen partial pressure ratio of 3:1 within 5 minutes after the start of sputtering, and an oxide transition layer with a gradient oxygen content is deposited on the surface of the pure Cr base layer.

[0076] 3.2) maintaining the argon-oxygen partial pressure ratio at 3:1, and continuing to sputter the Al target and the Cr target simultaneously under the above-mentioned magnetron sputtering conditions for 180 min, so as to further deposit an alloy oxide layer on the surface of the gradient-distributed oxide transition layer, and obtain a composite coating consisting of a pure Cr base layer, an oxide transition layer and an alloy oxide layer from the inside to the outside.

[0077] 3.3) After coating, stop ventilation and maintain vacuum until the substrate temperature is ≤60℃.

[0078] Step 4, annealing the composite coating to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides:

[0079] The annealing atmosphere is air, the heating rate is 5°C / min, the annealing temperature is 600°C, the holding time is 2h, and then the furnace is cooled to room temperature.

[0080] After testing, the thickness of the alloy oxide tritium barrier coating obtained in this embodiment is 2.93 μm. In addition, among the metal element components of the alloy oxide tritium barrier coating in this embodiment, the atomic percentage of aluminum is 21.8%, and the atomic percentage of chromium is 78.2%.

[0081] Example 3

[0082] This embodiment provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0083] Step 1: After polishing and cleaning the metal substrate, perform glow sputtering cleaning to obtain a clean metal substrate:

[0084] 1.1) In this embodiment, a 316L stainless steel substrate is used as a metal substrate, which is polished and cleaned to obtain a polished 316L stainless steel substrate.

[0085] 1.2) The polished metal substrate is dried and mounted on a workpiece turntable of a magnetron sputtering vacuum chamber, and two metal Al targets and one metal chromium target are placed on target positions in the magnetron sputtering vacuum chamber, respectively. The metal Al target is connected to a medium frequency power supply, and the metal Cr target is connected to a DC pulse power supply.

[0086] 1.3) Evacuate the vacuum chamber of the magnetron sputtering equipment to 5×10 -3 Pa, and then argon gas was introduced to control the gas pressure to 0.5 Pa. The bias voltage applied to the substrate was -800 V, and the substrate was cleaned by glow sputtering for 10 minutes to obtain a clean metal substrate.

[0087] Step 2: In an argon atmosphere, a layer of pure Cr primer is deposited on the surface of a clean metal substrate by sputtering a metal Cr target using magnetron sputtering technology:

[0088] Argon gas was introduced into the vacuum chamber, the Cr target was turned on, the working gas pressure was controlled to be 0.6 Pa, the bias voltage applied to the substrate was -150 V, the sputtering time was 10 min, and a layer of pure Cr primer was deposited on the surface of the clean metal substrate.

[0089] Step 3, using magnetron sputtering technology, sequentially depositing an oxide transition layer and an alloy oxide layer:

[0090] 3.1) By introducing argon and oxygen into the vacuum chamber of the magnetron sputtering equipment, the magnetron sputtering technology is adopted. In the dual power supply mode of the medium frequency power supply and the DC pulse power supply, the working gas pressure is controlled to be 0.6 Pa, the bias voltage applied to the substrate is -200 V, the metal Al target and the metal Cr target are turned on, the total power is adjusted to 4000 W, and the power ratio of the metal Al target and the metal Cr target is 1:1. By sputtering the Al target and the Cr target at the same time, the argon flux is kept constant during sputtering, and the oxygen flux is gradually increased to an argon-oxygen partial pressure ratio of 3:1 within 5 minutes after the start of sputtering, and an oxide transition layer with a gradient oxygen content is deposited on the surface of the pure Cr base layer.

[0091] 3.2) maintaining the argon-oxygen partial pressure ratio at 3:1, and continuing to sputter the Al target and the Cr target simultaneously under the above-mentioned magnetron sputtering conditions for 180 min, so as to further deposit an alloy oxide layer on the surface of the gradient-distributed oxide transition layer, and obtain a composite coating consisting of a pure Cr base layer, an oxide transition layer and an alloy oxide layer from the inside to the outside.

[0092] 3.3) After coating, stop ventilation and maintain vacuum until the substrate temperature is ≤60℃.

[0093] Step 4, annealing the composite coating to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides:

[0094] The annealing atmosphere is air, the heating rate is 5°C / min, the annealing temperature is 600°C, the holding time is 2h, and then the furnace is cooled to room temperature.

[0095] After testing, the thickness of the alloy oxide tritium barrier coating obtained in this embodiment is 2.89 μm. In addition, among the metal element components of the alloy oxide tritium barrier coating in this embodiment, the atomic percentage of aluminum is 45.8%, and the atomic percentage of chromium is 54.2%.

[0096] Example 4

[0097] This embodiment provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0098] Step 1: After polishing and cleaning the metal substrate, perform glow sputtering cleaning to obtain a clean metal substrate:

[0099] 1.1) In this embodiment, a 304L stainless steel substrate is used as a metal substrate, which is polished and cleaned to obtain a polished 304L stainless steel substrate.

[0100] 1.2) The polished metal substrate is dried and mounted on a workpiece turntable of a magnetron sputtering vacuum chamber, and two metal Al targets and one metal chromium target are placed on target positions in the magnetron sputtering vacuum chamber, respectively. The metal Al target is connected to a medium frequency power supply, and the metal Cr target is connected to a DC pulse power supply.

[0101] 1.3) Evacuate the vacuum chamber of the magnetron sputtering equipment to 5×10 -3 Pa, and then argon gas was introduced to control the gas pressure to 0.5 Pa. The bias voltage applied to the substrate was -800 V, and the substrate was cleaned by glow sputtering for 10 minutes to obtain a clean metal substrate.

[0102] Step 2: In an argon atmosphere, a layer of pure Cr primer is deposited on the surface of a clean metal substrate by sputtering a metal Cr target using magnetron sputtering technology:

[0103] Argon gas was introduced into the vacuum chamber, the Cr target was turned on, the working gas pressure was controlled to be 0.6 Pa, the bias voltage applied to the substrate was -150 V, the sputtering time was 10 min, and a layer of pure Cr primer was deposited on the surface of the clean metal substrate.

[0104] Step 3, using magnetron sputtering technology, sequentially depositing an oxide transition layer and an alloy oxide layer:

[0105] 3.1) By introducing argon and oxygen into the vacuum chamber of the magnetron sputtering equipment, the magnetron sputtering technology is adopted. In the dual power supply mode of the medium frequency power supply and the DC pulse power supply, the working gas pressure is controlled to be 0.6 Pa, the bias voltage applied to the substrate is -200 V, the metal Al target and the metal Cr target are turned on, the total power is adjusted to 3000 W, and the power ratio of the metal Al target to the metal Cr target is 2:1. By sputtering the Al target and the Cr target at the same time, the argon flux is kept constant during sputtering, and the oxygen flux is gradually increased to an argon-oxygen partial pressure ratio of 4:1 within 5 minutes after the start of sputtering, and an oxide transition layer with a gradient oxygen content is deposited on the surface of the pure Cr base layer.

[0106] 3.2) maintaining the argon-oxygen partial pressure ratio at 4:1, and continuing to sputter the Al target and the Cr target simultaneously under the above-mentioned magnetron sputtering conditions for 180 min, so as to further deposit an alloy oxide layer on the surface of the gradient-distributed oxide transition layer, and obtain a composite coating consisting of a pure Cr base layer, an oxide transition layer and an alloy oxide layer from the inside to the outside.

[0107] 3.3) After coating, stop ventilation and maintain vacuum until the substrate temperature is ≤60℃.

[0108] Step 4, performing annealing treatment 1 on the composite coating to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides:

[0109] The annealing atmosphere is air, the heating rate is 5°C / min, the annealing temperature is 650°C, the holding time is 2h, and then the sample is cooled to room temperature in the furnace.

[0110] After testing, the thickness of the alloy oxide tritium barrier coating obtained in this embodiment is 3.07 μm. In addition, among the metal element components of the alloy oxide tritium barrier coating in this embodiment, the atomic percentage of aluminum is 54.3%, and the atomic percentage of chromium is 45.7%.

[0111] Example 5

[0112] This embodiment provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0113] Step 1: After polishing and cleaning the metal substrate, perform glow sputtering cleaning to obtain a clean metal substrate:

[0114] 1.1) In this embodiment, a 304L stainless steel substrate is used as a metal substrate, which is polished and cleaned to obtain a polished 304L stainless steel substrate.

[0115] 1.2) The polished metal substrate is dried and mounted on a workpiece turntable of a magnetron sputtering vacuum chamber, and two metal Al targets and one metal chromium target are placed on target positions in the magnetron sputtering vacuum chamber, respectively. The metal Al target is connected to a medium frequency power supply, and the metal Cr target is connected to a DC pulse power supply.

[0116] 1.3) Evacuate the vacuum chamber of the magnetron sputtering equipment to 5×10 -3 Pa, and then argon gas was introduced to control the gas pressure to 0.5 Pa. The bias voltage applied to the substrate was -800 V, and the substrate was cleaned by glow sputtering for 10 minutes to obtain a clean metal substrate.

[0117] Step 2: In an argon atmosphere, a layer of pure Cr primer is deposited on the surface of a clean metal substrate by sputtering a metal Cr target using magnetron sputtering technology:

[0118] Argon gas was introduced into the vacuum chamber, the Cr target was turned on, the working gas pressure was controlled to be 0.6 Pa, the bias voltage applied to the substrate was -150 V, the sputtering time was 10 min, and a layer of pure Cr primer was deposited on the surface of the clean metal substrate.

[0119] Step 3, using magnetron sputtering technology, sequentially depositing an oxide transition layer and an alloy oxide layer:

[0120] 3.1) By introducing argon and oxygen into the vacuum chamber of the magnetron sputtering equipment, using magnetron sputtering technology, in the dual power supply mode of the medium frequency power supply and the DC pulse power supply, the working gas pressure is controlled to be 0.6 Pa, the bias voltage applied to the substrate is -200 V, the metal Al target and the metal Cr target are turned on, the total power is adjusted to 5000 W, and the power ratio of the metal Al target to the metal Cr target is 1:1. By sputtering the Al target and the Cr target at the same time, the argon flux is kept constant during sputtering, and the oxygen flux is gradually increased to an argon-oxygen partial pressure ratio of 3:1 within 5 minutes after the start of sputtering, and an oxide transition layer with a gradient oxygen content is deposited on the surface of the pure Cr base layer.

[0121] 3.2) maintaining the argon-oxygen partial pressure ratio at 3:1, and continuing to sputter the Al target and the Cr target simultaneously under the above-mentioned magnetron sputtering conditions for 180 min, so as to further deposit an alloy oxide layer on the surface of the gradient-distributed oxide transition layer, and obtain a composite coating consisting of a pure Cr base layer, an oxide transition layer and an alloy oxide layer from the inside to the outside.

[0122] 3.3) After coating, stop ventilation and maintain vacuum until the substrate temperature is ≤60℃.

[0123] Step 4, performing annealing treatment 1 on the composite coating to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides:

[0124] The annealing atmosphere is air, the heating rate is 5°C / min, the annealing temperature is 700°C, the holding time is 3h, and then the furnace is cooled to room temperature.

[0125] After testing, the thickness of the alloy oxide tritium barrier coating obtained in this embodiment is 3.57 μm. In addition, among the metal element components of the alloy oxide tritium barrier coating in this embodiment, the atomic percentage of aluminum is 38.2%, and the atomic percentage of chromium is 61.8%.

[0126] Comparative Example 1

[0127] This comparative example provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0128] Step 1: After polishing and cleaning the metal substrate, perform glow sputtering cleaning to obtain a clean metal substrate:

[0129] 1.1) In this embodiment, a 316L stainless steel substrate is used as a metal substrate, which is polished and cleaned to obtain a polished 316L stainless steel substrate.

[0130] 1.2) The polished metal substrate is dried and mounted on a workpiece turntable of a magnetron sputtering vacuum chamber, and two metal Al targets and one metal Cr target are placed on target positions in the magnetron sputtering vacuum chamber, respectively. The metal Al target is connected to a medium frequency power supply, and the metal Cr target is connected to a DC pulse power supply.

[0131] 1.3) Evacuate the vacuum chamber of the magnetron sputtering equipment to 5×10 -3 Pa, and then argon gas was introduced to control the gas pressure to 0.5 Pa. The bias voltage applied to the substrate was -800 V, and the substrate was cleaned by glow sputtering for 10 minutes to obtain a clean metal substrate.

[0132] Step 2: In an argon atmosphere, a layer of pure Cr primer is deposited on the surface of a clean metal substrate by sputtering a metal Cr target using magnetron sputtering technology:

[0133] Argon gas was introduced into the vacuum chamber, the Cr target was turned on, the working gas pressure was controlled to be 0.6 Pa, the bias voltage applied to the substrate was -150 V, the sputtering time was 10 min, and a layer of pure Cr primer was deposited on the surface of the clean metal substrate.

[0134] Step 3, using magnetron sputtering technology, sequentially depositing an oxide transition layer and an alloy oxide layer:

[0135] 3.1) By introducing argon and oxygen into the vacuum chamber of the magnetron sputtering equipment, the magnetron sputtering technology is adopted. In the dual power supply mode of the medium frequency power supply and the DC pulse power supply, the working gas pressure is controlled to be 0.6 Pa, the bias voltage applied to the substrate is -200 V, the metal Al target and the metal Cr target are turned on, the total power is adjusted to 4000 W, and the power ratio of the metal Al target to the metal Cr target is 3:1. By sputtering the Al target and the Cr target at the same time, the argon flux is kept constant during sputtering, and the oxygen flux is gradually increased to an argon-oxygen partial pressure ratio of 3:1 within 5 minutes after the start of sputtering, and an oxide transition layer with a gradient oxygen content is deposited on the surface of the pure Cr base layer.

[0136] 3.2) maintaining the argon-oxygen partial pressure ratio at 3:1, and continuing to sputter the Al target and the Cr target simultaneously under the above-mentioned magnetron sputtering conditions for 180 min, so as to further deposit an alloy oxide layer on the surface of the gradient-distributed oxide transition layer, and obtain a composite coating consisting of a pure Cr base layer, an oxide transition layer and an alloy oxide layer from the inside to the outside.

[0137] 3.3) After coating, stop ventilation and maintain vacuum until the substrate temperature is ≤60℃.

[0138] The difference between this comparative example and Example 1 is only that:

[0139] This comparative example does not undergo annealing treatment, that is, this comparative example uses the composite coating formed on the surface of the metal substrate as the tritium barrier coating.

[0140] After testing, the thickness of the alloy oxide tritium barrier coating obtained in this comparative example is 2.86 μm. In addition, in the metal element composition of the alloy oxide tritium barrier coating in this comparative example, the atomic percentage of aluminum element is 62.3%, and the atomic percentage of chromium element is 27.7%.

[0141] Comparative Example 2

[0142] This comparative example provides a method for preparing an alloy oxide tritium barrier coating, comprising the following steps:

[0143] Step 1: After polishing and cleaning the metal substrate, perform glow sputtering cleaning to obtain a clean metal substrate:

[0144] 1.1) In this embodiment, a 316L stainless steel substrate is used as a metal substrate, which is polished and cleaned to obtain a polished 316L stainless steel substrate.

[0145] 1.2) The polished metal substrate is dried and mounted on a workpiece turntable of a magnetron sputtering vacuum chamber, and two metal Al targets and one metal chromium target are placed on target positions in the magnetron sputtering vacuum chamber, respectively. The metal Al target is connected to a medium frequency power supply, and the metal Cr target is connected to a DC pulse power supply.

[0146] 1.3) Evacuate the vacuum chamber of the magnetron sputtering equipment to 5×10 -3 Pa, and then argon gas was introduced to control the gas pressure to 0.5 Pa. The bias voltage applied to the substrate was -800 V, and the substrate was cleaned by glow sputtering for 10 minutes to obtain a clean metal substrate.

[0147] Step 2: In an argon atmosphere, a layer of pure Cr primer is deposited on the surface of a clean metal substrate by sputtering a metal Cr target using magnetron sputtering technology:

[0148] Argon gas was introduced into the vacuum chamber, the Cr target was turned on, the working gas pressure was controlled to be 0.6 Pa, the bias voltage applied to the substrate was -150 V, the sputtering time was 10 min, and a layer of pure Cr primer was deposited on the surface of the clean metal substrate.

[0149] Step 3, using magnetron sputtering technology to deposit the alloy oxide layer:

[0150] 3.1) Argon and oxygen are introduced into the vacuum chamber of the magnetron sputtering equipment to control the argon-oxygen partial pressure ratio to 3:1. Magnetron sputtering technology is used. In the dual power supply mode of the medium frequency power supply and the DC pulse power supply, the working gas pressure is controlled to be 0.6 Pa, the bias voltage applied to the substrate is -200 V, the metal Al target and the metal Cr target are turned on, the total power is adjusted to 4000 W, and the power ratio of the metal Al target to the metal Cr target is 1:1. The Al target and the Cr target are sputtered simultaneously, and the sputtering deposition time is 180 min to further deposit an alloy oxide layer on the surface of the pure Cr base layer, so as to obtain a composite coating consisting of a pure Cr base layer and an alloy oxide layer from the inside to the outside.

[0151] 3.3) After coating, stop ventilation and maintain vacuum until the substrate temperature is ≤60℃.

[0152] Step 4, annealing the composite coating to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides:

[0153] The annealing atmosphere is air, the heating rate is 5°C / min, the annealing temperature is 600°C, the holding time is 2h, and then the furnace is cooled to room temperature.

[0154] The difference between this comparative example and Example 3 is only that:

[0155] In this comparative example, no gradient oxidation transition layer was prepared.

[0156] After testing, the thickness of the alloy oxide tritium barrier coating obtained in this comparative example is 3.12 μm. In addition, among the metal element components of the alloy oxide tritium barrier coating in this comparative example, the atomic percentage of aluminum element is 42.2%, and the atomic percentage of chromium element is 57.8%.

[0157] Experimental Section

[0158] (I) Microscopic morphology test

[0159] The present invention takes the coatings of Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2 as examples, and performs scanning electron microscope tests respectively, and the test results are as follows: Figure 1-Figure 6 shown.

[0160] in, Figure 1 This is a surface scanning electron microscope image of the coating of Comparative Example 1, Figure 2 is a cross-sectional scanning electron microscope image of the coating of Comparative Example 1, Figure 3 This is a surface scanning electron microscope image of the coating of Comparative Example 2. Figure 4 is a surface scanning electron microscope image of the coating of Example 1, Figure 5 This is a surface scanning electron microscope image of the coating of Example 2. Figure 6 Surface scanning electron microscope image of the coating of Example 3.

[0161] Depend on Figure 1 and Figure 2 It can be seen that the coating components on the surface of the coating without annealing in Comparative Example 1 are mainly present in the form of amorphous oxide particles, and there are obvious pores between the amorphous oxide particles, and the coating surface density is poor. However, there is a metal phase residue in the gradient oxidation transition layer in the middle of the coating, and the middle phase of the coating is more uniform and dense than the coating surface.

[0162] Depend on Figure 3 It can be seen that compared with Figure 1 It can be seen that after annealing, no oxide particles exist on the coating surface of the non-gradient oxide transition layer, which indicates that annealing is indeed beneficial to promote the conversion of amorphous oxides on the coating surface into crystalline oxides. However, obvious cracks appeared on the coating surface of Comparative Example 2, and peeling occurred macroscopically.

[0163] Depend on Figure 4 It can be seen that the coating components on the coating surface of Example 1 are mainly present in the form of dense crystalline oxides. Figure 3 and Figure 1 It can be seen that Example 1 performs annealing treatment on the basis of the coating of Comparative Example 1, so that the oxide on the surface of the coating is transformed from an amorphous state to a crystalline state, thereby improving the tissue density of the coating. This shows that annealing treatment plays a very important role in promoting the transformation of the oxide from an amorphous state to a crystalline state, thereby improving the tissue density of the coating, and the crystalline metal oxide on the surface is beneficial to improving the tritium and hydrogen barrier properties of the substrate.

[0164] Depend on Figure 5It can be seen that the coating surface of Example 2 is similar to that of Example 1, and both have dense texture.

[0165] Depend on Figure 6 It can be seen that the coating surface of Example 3 is similar to that of Example 1, and both have dense texture. Figure 6 and Figure 3 It can be seen that after adding a gradient oxidation transition layer to Example 3 on the basis of Comparative Example 2, the bonding between the coating and the substrate is significantly improved, avoiding the occurrence of thermal mismatch effect, which indicates that the formation of the gradient oxidation transition layer has an important influence on improving the bonding strength between the coating and the substrate.

[0166] (ii) XRD test

[0167] The present invention takes the coating on the surface of Example 1 as an example and performs XRD test on it, and the test results are as follows Figure 7 shown.

[0168] Figure 7 This is the XRD spectrum of the coating on the surface of Example 1. It can be seen that the coating on the surface of Example 1 contains crystalline chromium oxide and does not contain hydrogen, which indicates that annealing can indeed promote the transformation of the oxide from an amorphous state to a crystalline state, thereby improving the density of the coating structure, and further helping to improve the tritium and hydrogen barrier properties of the substrate.

[0169] (III) Tritium resistance performance test

[0170] The present invention adopts a hydrogen barrier performance test to replace the tritium barrier test. Referring to the method in the prior art CN115747775A, the present invention uses a gas-driven hydrogen permeation test device and an electrochemical hydrogen permeation device to evaluate the hydrogen barrier and hydrogen permeation barrier effects of the coatings prepared in Examples 1 to 5 and Comparative Example 2. The results show that the hydrogen permeation barrier factors of the coatings prepared in Examples 1 to 5 of the present invention are all >200, which indicates that the alloy oxide tritium barrier coating prepared by the preparation method of the present invention has good hydrogen barrier properties. The hydrogen permeation barrier factor of Comparative Example 2 is 43, which is greatly reduced compared to the hydrogen permeation barrier factors of Examples 1 to 5, which further verifies that the formation of the gradient oxidation transition layer has an important influence on improving the bonding strength between the coating and the substrate.

[0171] Obviously, the above embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A method for preparing an alloy oxide tritium barrier coating, characterized in that: The following steps are involved: Pretreatment of metal substrate: After polishing and cleaning the metal substrate, glow sputtering cleaning is performed to obtain a clean metal substrate; Depositing a pure Cr base layer: In an argon atmosphere, magnetron sputtering technology is used to deposit a layer of pure Cr base layer on the surface of a clean metal substrate by sputtering a metal Cr target; Adopting magnetron sputtering technology, depositing an oxide transition layer and an alloy oxide layer in sequence: introducing argon gas and oxygen, adopting magnetron sputtering technology, in a dual power supply mode, by sputtering an Al target and a Cr target simultaneously, and gradually increasing the oxygen flux to a stable flow rate within 5 minutes after the start of sputtering, so as to form a gradient-distributed oxide transition layer on the surface of the pure Cr base layer; Subsequently, the Al target and the Cr target are sputtered simultaneously while maintaining the flow ratio of argon gas to oxygen gas, so as to deposit an alloy oxide layer on the surface of the oxidation transition layer, so as to form a composite coating of a pure Cr base layer, an oxidation transition layer and an alloy oxide layer from the inside to the outside on the surface of the metal substrate; Annealing treatment: the composite coating is subjected to annealing treatment to transform the oxide on the surface of the composite coating from an amorphous state to a crystalline state, thereby obtaining an alloy oxide tritium barrier coating containing crystalline oxides.

2. The preparation method according to claim 1, characterized in that When depositing the oxide transition layer and the alloy oxide layer, the metal Al target is sputtered in a medium frequency power supply mode, and the metal Cr target is sputtered in a direct current pulse power supply mode.

3. The preparation method according to claim 1, characterized in that: When the oxygen flux reaches a stable flow rate, the flow ratio of argon to oxygen is 3 to 7:

1.

4. The preparation method according to claim 1, characterized in that: When the oxidation transition layer and the alloy oxide layer are deposited, the gas pressure is 0.1Pa to 1Pa, and the bias voltage applied to the substrate is -30V to 200V.

5. The preparation method according to claim 1, characterized in that: When depositing the alloy oxide layer, the deposition time is 10 min to 600 min.

6. The preparation method according to claim 1, characterized in that: When depositing the oxide transition layer and the alloy oxide layer, the total sputtering power of the Al target and the Cr target is 100W to 5000W.

7. The preparation method according to claim 1, characterized in that: When depositing the pure Cr base layer, the gas pressure is 0.2Pa to 1.6Pa, and the bias voltage applied to the substrate is -30V to 300V; The thickness of the pure Cr base layer is 50nm to 200nm.

8. The preparation method according to claim 1, characterized in that: During the glow sputtering cleaning treatment, the vacuum is first evacuated to <0.005Pa, and then argon gas is introduced to a pressure of 0.4Pa to 2.0Pa. A bipolar pulse power supply is used, and the bias voltage applied to the substrate is -200V to 1000V. The treatment is performed for at least 5 minutes.

9. The preparation method according to claim 1, characterized in that: The annealing temperature of the annealing treatment is 200° C. to 800° C., and the annealing holding time is 10 min to 360 min.

10. An alloy oxide tritium barrier coating prepared by the preparation method according to any one of claims 1 to 9, characterized in that: In the alloy oxide tritium barrier coating, the atomic ratio of Al element to Cr element is 1-2:1-9.

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