Method for prolonging service life of aluminum alloy vacuum valve

Abstract

The invention provides a method for prolonging the service life of an aluminum alloy vacuum valve, which comprises the following steps: sequentially carrying out degreasing treatment, alkali washing, acid washing, first anodic oxidation treatment and second anodic oxidation treatment on the aluminum alloy vacuum valve to obtain the aluminum alloy vacuum valve with an oxidation film on the surface. The method is simple in process and convenient to operate, an oxidation film with the thickness of 16-20 mm is formed on the surface of the aluminum alloy vacuum valve, the corrosion resistance, abrasion resistance and voltage resistance of the aluminum alloy vacuum valve are improved, the service life is prolonged, and the method is suitable for large-scale popularization.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum valves, and in particular to a method for improving the service life of an aluminum alloy vacuum valve. Background Art

[0002] The working principle of the pneumatic propulsion vacuum valve is to control the opening and closing of the valve by converting compressed gas into mechanical motion through the actuator. The pneumatic propulsion vacuum valve has good sealing, corrosion resistance, temperature resistance, and wear resistance, and can be used in vacuum and complex working environments.

[0003] CN102162544A discloses an electric vacuum valve, comprising: a valve portion having a first port and a second port, a valve chamber and a valve seat; a feed thread connected to a stepper motor; a shaft; a feed thread mechanism consisting of a feed thread and the shaft; an anti-rotation unit to prevent the shaft from rotating; a valve core installed at the front end of the shaft; and a restoring spring, wherein, when a power outage occurs, a positioning torque is generated between the stator and the rotor of the stepper motor, and the thrust of the restoring spring is greater than the resistance formed by converting the positioning torque through the feed thread mechanism, thereby closing the valve.

[0004] CN1103176A discloses a vacuum valve control device and a vacuum valve, the vacuum valve comprising: a pressure control chamber for supplying vacuum force to a valve body, which can connect the valve working chamber with a vacuum channel; a detection valve, which can introduce vacuum force into the pressure control chamber; a piston directly driven by a liquid detection diaphragm, wherein the piston drives the detection valve; and an opening time regulating valve, which is opened to make the vacuum introduced into the pressure control chamber disappear, wherein the opening time is automatically controlled by the vacuum in the vacuum discharge pipe. Moreover, when the pressure inside the liquid level detection pipe joint is rapidly reduced, the pressure in the pressure regulating chamber is rapidly discharged through the gap formed between the damping diaphragm and the support part.

[0005] CN1953117A discloses a vacuum valve and a method for manufacturing the vacuum valve, wherein the vacuum valve comprises an airtight container having an insulating cylinder, a movable side end plate and a fixed side end plate and accommodating a movable contact element and a fixed contact element relative to each other. The movable contact element is supported by a bellows, and its movement performs the switching action of the contact while maintaining the airtightness of the airtight container. The bellows used is a seam-type bellows without nickel plating. The nickel plating layer and the nickel plating layer are respectively formed on the movable side end plate and the cover to be joined with the bellows. The end of the bellows is welded to the movable side end plate and the cover at the welding seam and with silver solder to seal the container.

[0006] However, the surface of the above vacuum valve is susceptible to corrosion, oxidation and wear, and its service life needs to be further improved. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides a method for improving the service life of an aluminum alloy vacuum valve. The service life of the aluminum alloy vacuum valve is improved by sequentially performing degreasing treatment, alkali washing, acid washing and two anodizing treatments on the aluminum alloy vacuum valve. The method is simple and convenient to operate and can be realized in industrial production.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] The present invention provides a method for improving the service life of an aluminum alloy vacuum valve, the method comprising:

[0010] The aluminum alloy vacuum valve is sequentially subjected to degreasing treatment, alkali washing, pickling, first anodizing treatment and second anodizing treatment to obtain an aluminum alloy vacuum valve having an oxide film on the surface;

[0011] The thickness of the oxide film is 16-20 mm; the aluminum alloy vacuum valve with the oxide film on the surface has a withstand voltage of 0.59-0.74 KV and an impedance of 38.57-48.22 KΩ.

[0012] The method for improving the service life of the aluminum alloy vacuum valve of the present invention is simple to operate. First, the aluminum alloy vacuum valve is degreased to remove the oil stains on the surface; then, alkali washing is performed to remove the aluminum powder and the oxide layer on the surface; then, pickling is performed to remove the aluminum hydroxide, the reaction residue on the surface; and then two anodizing treatments are performed to form a dense, uniform oxide film with a thickness of 16 to 20 mm on the surface of the aluminum alloy vacuum valve, thereby greatly improving the corrosion resistance and wear resistance of the aluminum alloy vacuum valve, and further improving the service life of the vacuum valve. When only one anodizing treatment is performed, the thickness of the oxide film will be less than 16 mm, and there will be a problem of uneven oxide film thickness.

[0013] The thickness of the oxide film of the present invention is 16 to 20 mm, for example, it can be 16 mm, 16.5 mm, 17 mm, 18 mm, 19 mm, 19.5 mm or 20 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0014] The aluminum alloy vacuum valve having an oxide film on the surface has a withstand voltage of 0.59 to 0.74 KV, for example, 0.59 KV, 0.6 KV, 0.62 KV, 0.65 KV, 0.68 KV, 0.7 KV or 0.74 KV, but is not limited to the listed values, and other values ​​not listed within the range are also applicable;

[0015] The impedance is 38.57 to 48.22 KΩ, for example, it can be 38.57 KΩ, 38.6 KΩ, 38.8 KΩ, 40 KΩ, 41 KΩ, 45 KΩ or 48.22 KΩ, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0016] Preferably, the aluminum alloy vacuum valve comprises a pneumatically propelled aluminum alloy vacuum valve.

[0017] Preferably, the material of the aluminum alloy vacuum valve includes 6082 aluminum alloy.

[0018] Preferably, the degreasing liquid used in the degreasing treatment is a nitric acid solution.

[0019] Preferably, the concentration of the degreasing liquid is 110-150 g / L, for example, it can be 110 g / L, 115 g / L, 120 g / L, 130 g / L, 140 g / L, 145 g / L, 148 g / L or 150 g / L, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] Preferably, the degreasing treatment time is 10 to 15 minutes, for example, it can be 10 minutes, 10.5 minutes, 11 minutes, 11.5 minutes, 12 minutes, 13 minutes, 14 minutes or 15 minutes, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0021] Preferably, a first water wash is performed after the degreasing treatment.

[0022] Preferably, the alkali solution used in the alkali washing is sodium hydroxide solution.

[0023] Preferably, the concentration of the alkali solution is 40-90 g / L, for example, it can be 40 g / L, 50 g / L, 55 g / L, 60 g / L, 65 g / L, 70 g / L, 80 g / L or 90 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0024] Preferably, the alkali washing time is 2 to 7 minutes, for example, it can be 2 minutes, 2.5 minutes, 3 minutes, 3.5 minutes, 4 minutes, 5 minutes, 6 minutes or 7 minutes, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0025] Preferably, a second water wash is performed after the alkali wash.

[0026] Preferably, the acid solution used for pickling is a nitric acid solution.

[0027] Preferably, the concentration of the acid solution is 100-150 g / L, for example, it can be 100 g / L, 105 g / L, 110 g / L, 115 g / L, 120 g / L, 130 g / L, 140 g / L or 150 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] Preferably, the pickling time is 1 to 6 minutes, for example, 1 minute, 1.5 minutes, 2 minutes, 3 minutes, 3.5 minutes, 4 minutes, 5 minutes or 6 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0029] Preferably, a third water wash is performed after the acid wash.

[0030] Preferably, the anodizing solutions used in the first anodizing treatment and the second anodizing treatment each independently include a sulfuric acid solution.

[0031] Preferably, the concentration of the anodizing solution is 150-200 g / L, for example, it can be 150 g / L, 155 g / L, 160 g / L, 170 g / L, 175 g / L, 180 g / L, 190 g / L or 200 g / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0032] Preferably, the voltage of the first anodizing treatment is 7 to 12 V, for example, 7 V, 8 V, 9 V, 10 V, 11 V, 11.5 V or 12 V, etc., but is not limited to the listed values, and other values ​​not listed within the range are also applicable;

[0033] The holding time is 3 to 8 minutes, for example, 3 minutes, 3.5 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 7.5 minutes or 8 minutes, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable;

[0034] The boost rate is 1 to 6 V / min, for example, 1 V / min, 1.5 V / min, 2 V / min, 3 V / min, 4 V / min, 5 V / min or 6 V / min, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0035] The present invention preferably has a voltage of 7 to 12 V for the first anodizing treatment, which will preferentially form a thin and uniform oxide film, referred to as a base film, to facilitate the subsequent formation of an oxide film of a specific thickness. When the voltage of the first anodizing treatment is low, the base film cannot be formed, thereby affecting the formation of the oxide film; when the voltage of the first anodizing treatment is high, the base film will decompose, which will also affect the formation of the oxide film.

[0036] The holding time of the first anodizing treatment of the present invention is 3 to 8 minutes, and the thickness of the formed base film is uniform, which will improve the overall quality of the anodized film. When the holding time of the first anodizing treatment is short, the base film will be uneven; when the holding time of the first anodizing treatment is long, the process cost of the anodizing treatment will increase.

[0037] Preferably, the voltage of the second anodizing treatment is 18 to 23 V, for example, 18 V, 19 V, 20 V, 21 V, 21.5 V, 22 V or 23 V, but is not limited to the listed values, and other values ​​not listed within the range are also applicable;

[0038] The holding time is 30 to 80 minutes, for example, 30 minutes, 40 minutes, 50 minutes, 60 minutes, 70 minutes, 75 minutes or 80 minutes, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable;

[0039] The boost rate is 1 to 6 V / min, for example, 1 V / min, 1.5 V / min, 2 V / min, 3 V / min, 4 V / min, 5 V / min or 6 V / min, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0040] The voltage of the second anodizing treatment of the present invention is 18 to 23V, which is higher than the voltage of the first anodizing treatment of 7 to 12V. In this way, a new oxide film will continue to be formed on the basis of the oxide film produced by the first anodizing treatment, so that the oxide film increases in thickness in all directions. If the voltage of the second anodizing treatment is lower than the voltage of the first anodizing treatment, a new oxide film will not be formed, resulting in a thinner oxide film on the surface of the aluminum alloy vacuum valve, and the corrosion resistance, wear resistance and voltage resistance of the aluminum alloy vacuum valve are all poor.

[0041] The holding time of the second anodizing treatment of the present invention is 30 to 80 minutes. When the holding time of the second anodizing treatment is short, the oxide film on the surface of the aluminum alloy vacuum valve will be thinner; when the holding time of the second anodizing treatment is long, the oxide film on the surface of the aluminum alloy vacuum valve will tend to crack, thereby reducing the quality of the oxide film.

[0042] Preferably, after the second anodizing treatment, the aluminum alloy vacuum valve is sealed.

[0043] As a preferred technical solution of the present invention, the method comprises the following steps:

[0044] (1) a pneumatically driven vacuum valve made of 6082 aluminum alloy is subjected to a degreasing treatment for 10 to 15 minutes; the degreasing liquid used in the degreasing treatment is a nitric acid solution with a concentration of 110 to 150 g / L; and a first water washing is performed after the degreasing treatment is completed;

[0045] (2) using a sodium hydroxide solution with a concentration of 40 to 90 g / L for 2 to 7 minutes, and then performing a second water wash;

[0046] (3) using a nitric acid solution with a concentration of 100 to 150 g / L for pickling for 1 to 6 minutes, and then performing a third water wash after the pickling;

[0047] (4) using a sulfuric acid solution with a concentration of 150 to 200 g / L for a first anodizing treatment; the voltage of the first anodizing treatment is 7 to 12 V, the holding time is 3 to 8 min, and the voltage increase rate is 1 to 6 V / min;

[0048] (5) After a second anodizing treatment is performed using a sulfuric acid solution with a concentration of 150 to 200 g / L, the aluminum alloy vacuum valve is sealed to obtain an aluminum alloy vacuum valve with an oxide film on the surface;

[0049] The voltage of the second anodizing treatment is 18 to 23 V, the holding time is 30 to 80 min, and the voltage increase rate is 1 to 6 V / min;

[0050] The thickness of the oxide film is 16-20 mm; the aluminum alloy vacuum valve with the oxide film on the surface has a withstand voltage of 0.59-0.74 KV and an impedance of 38.57-48.22 KΩ.

[0051] Compared with the prior art, the present invention has at least the following beneficial effects:

[0052] The method for improving the service life of an aluminum alloy vacuum valve provided by the present invention has a simple process and is easy to operate. Through two specific anodizing treatments, an oxide film with a thickness of 16 to 20 mm is formed on the surface of the aluminum alloy vacuum valve, thereby improving the corrosion resistance, wear resistance and voltage resistance of the aluminum alloy vacuum valve, extending the service life and reducing the procurement cost. DETAILED DESCRIPTION

[0053] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0054] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0055] The following are typical but non-limiting embodiments of the present invention:

[0056] Example 1

[0057] This embodiment provides a method for improving the service life of an aluminum alloy vacuum valve, the method comprising the following steps:

[0058] (1) a pneumatically driven vacuum valve made of 6082 aluminum alloy was subjected to a degreasing treatment for 10 minutes; the degreasing liquid used in the degreasing treatment was a nitric acid solution with a concentration of 150 g / L; and a first water washing was performed after the degreasing treatment;

[0059] (2) using a sodium hydroxide solution with a concentration of 50 g / L for 5 min, and then performing a second water wash;

[0060] (3) using a nitric acid solution with a concentration of 150 g / L for pickling for 2 min, and then performing a third water wash after the pickling;

[0061] (4) performing a first anodizing treatment using a sulfuric acid solution having a concentration of 160 g / L; the voltage of the first anodizing treatment is 10 V, the holding time is 3 min, and the voltage increase rate is 5 V / min;

[0062] (5) After a second anodizing treatment using a sulfuric acid solution having a concentration of 160 g / L, the aluminum alloy vacuum valve is sealed to obtain an aluminum alloy vacuum valve having an oxide film on the surface;

[0063] The voltage of the second anodizing treatment is 18V, the holding time is 50min, and the voltage increasing rate is 1V / min.

[0064] Example 2

[0065] This embodiment provides a method for improving the service life of an aluminum alloy vacuum valve, the method comprising the following steps:

[0066] (1) A pneumatically driven vacuum valve made of 6082 aluminum alloy was degreased for 13 minutes; the degreasing liquid used in the degreasing treatment was a nitric acid solution with a concentration of 110 g / L; and a first water wash was performed after the degreasing treatment;

[0067] (2) using a sodium hydroxide solution with a concentration of 40 g / L for 2 min, and then performing a second water wash;

[0068] (3) using a nitric acid solution with a concentration of 100 g / L to perform pickling for 6 min, and then performing a third water wash after the pickling;

[0069] (4) performing a first anodizing treatment using a sulfuric acid solution having a concentration of 200 g / L; the voltage of the first anodizing treatment is 12 V, the holding time is 3 min, and the voltage increase rate is 6 V / min;

[0070] (5) After a second anodizing treatment is performed using a sulfuric acid solution with a concentration of 200 g / L, the aluminum alloy vacuum valve is sealed to obtain an aluminum alloy vacuum valve with an oxide film on the surface;

[0071] The voltage of the second anodizing treatment is 18V, the holding time is 80min, and the voltage increasing rate is 6V / min.

[0072] Example 3

[0073] This embodiment provides a method for improving the service life of an aluminum alloy vacuum valve, the method comprising the following steps:

[0074] (1) a pneumatically driven vacuum valve made of 6082 aluminum alloy was subjected to a degreasing treatment for 15 minutes; the degreasing liquid used in the degreasing treatment was a nitric acid solution with a concentration of 130 g / L; and a first water washing was performed after the degreasing treatment;

[0075] (2) using a sodium hydroxide solution with a concentration of 90 g / L for 7 min, and then performing a second water wash after the alkali wash;

[0076] (3) using a nitric acid solution with a concentration of 150 g / L to perform pickling for 1 min, and then performing a third water wash after the pickling;

[0077] (4) performing a first anodizing treatment using a sulfuric acid solution having a concentration of 150 g / L; the voltage of the first anodizing treatment is 7 V, the holding time is 8 min, and the voltage increase rate is 1 / min;

[0078] (5) After a second anodizing treatment using a sulfuric acid solution with a concentration of 150 g / L, the aluminum alloy vacuum valve is sealed to obtain an aluminum alloy vacuum valve having an oxide film on the surface;

[0079] The voltage of the second anodizing treatment is 23V, the holding time is 30min, and the voltage increasing rate is 1V / min.

[0080] Example 4

[0081] This embodiment provides a method for increasing the service life of an aluminum alloy vacuum valve. The method is the same as that of Embodiment 1 except that the voltage of the first anodizing treatment is 3V.

[0082] Example 5

[0083] This embodiment provides a method for increasing the service life of an aluminum alloy vacuum valve. The method is the same as that of Embodiment 1 except that the voltage of the first anodizing treatment is 18V, which is the same as the voltage of the second anodizing treatment.

[0084] Example 6

[0085] This embodiment provides a method for improving the service life of an aluminum alloy vacuum valve. The method is the same as that of Embodiment 1 except that the holding time of the first anodizing treatment is 2 minutes.

[0086] Comparative Example 1

[0087] This comparative example provides a method for increasing the service life of an aluminum alloy vacuum valve. The method is the same as Example 1 except that the alkaline washing step (2) is not performed.

[0088] Comparative Example 2

[0089] This comparative example provides a method for increasing the service life of an aluminum alloy vacuum valve. The method is the same as Example 1 except that the pickling step (3) is not performed.

[0090] Comparative Example 3

[0091] This comparative example provides a method for increasing the service life of an aluminum alloy vacuum valve. The method is the same as Example 1 except that the first anodizing treatment step (4) is not performed.

[0092] The thickness of the oxide film on the surface of the aluminum alloy vacuum valve obtained in the above embodiment and comparative example was tested by an eddy current thickness gauge;

[0093] The withstand voltage of the aluminum alloy vacuum valves obtained in the above embodiments and comparative examples was tested using a voltage breakdown tester;

[0094] The impedance of the aluminum alloy vacuum valves obtained in the above embodiments and comparative examples was tested using a resistivity tester, and the results are shown in Table 1.

[0095] Table 1

[0096]

[0097]

[0098] From Table 1 we can see that:

[0099] (1) It can be seen from Examples 1 to 3 that the method for improving the service life of an aluminum alloy vacuum valve provided by the present invention forms an oxide film of a specific thickness on the surface of the aluminum alloy vacuum valve, and the aluminum alloy vacuum valve has high voltage resistance and impedance, and a long service life; and the thickness of the oxide film of the aluminum alloy vacuum valve in Examples 1 to 3, the voltage resistance and impedance of the aluminum alloy vacuum valve fluctuate slightly, indicating that the method has certain stability;

[0100] (2) Combining Example 1 with Examples 4 to 6, it can be seen that the voltage of the first anodizing treatment in Example 4 is relatively low, the voltage of the first anodizing treatment in Example 5 is relatively high, and the holding time of the first anodizing treatment in Example 6 is relatively short. These changes in the process parameters of the first anodizing treatment all reduce the quality of the oxide film, resulting in lower oxide film thickness, withstand voltage and impedance data of the aluminum alloy vacuum valve;

[0101] (3) It can be seen from Example 1 and Comparative Examples 1 to 3 that Comparative Example 1 does not perform the alkaline washing step of step (2), Comparative Example 2 does not perform the acid washing step of step (3), and Comparative Example 4 does not perform the first anodizing treatment step of step (4), which are all not conducive to the formation of an oxide film on the surface of the aluminum alloy vacuum valve, resulting in a lower oxide film thickness as well as a lower withstand voltage and impedance of the aluminum alloy vacuum valve.

[0102] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that 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 shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for increasing the service life of an aluminum alloy vacuum valve, characterized in that: The method comprises: The aluminum alloy vacuum valve is sequentially subjected to degreasing treatment, alkali washing, pickling, first anodizing treatment and second anodizing treatment to obtain an aluminum alloy vacuum valve having an oxide film on the surface; The thickness of the oxide film is 16-20 mm; the aluminum alloy vacuum valve with the oxide film on the surface has a withstand voltage of 0.59-0.74 KV and an impedance of 38.57-48.22 KΩ.

2. The method according to claim 1, characterized in that The aluminum alloy vacuum valve comprises a pneumatically-propelled aluminum alloy vacuum valve; Preferably, the material of the aluminum alloy vacuum valve includes 6082 aluminum alloy.

3. The method according to claim 1 or 2, characterized in that: The degreasing liquid used in the degreasing treatment is a nitric acid solution; Preferably, the concentration of the degreasing liquid is 110-150 g / L; Preferably, the degreasing treatment time is 10 to 15 minutes; Preferably, a first water wash is performed after the degreasing treatment.

4. The method according to any one of claims 1 to 3, characterized in that: The alkali solution used in the alkali washing is a sodium hydroxide solution; Preferably, the concentration of the alkali solution is 40 to 90 g / L; Preferably, the alkali washing time is 2 to 7 minutes; Preferably, a second water wash is performed after the alkali wash.

5. The method according to any one of claims 1 to 4, characterized in that: The acid solution used in the pickling is a nitric acid solution; Preferably, the concentration of the acid solution is 100-150 g / L; Preferably, the pickling time is 1 to 6 minutes; Preferably, a third water wash is performed after the acid wash.

6. The method according to any one of claims 1 to 5, characterized in that: The anodizing solutions used in the first anodizing treatment and the second anodizing treatment each independently include a sulfuric acid solution; Preferably, the concentration of the anodizing solution is 150-200 g / L.

7. The method according to any one of claims 1 to 6, characterized in that: The voltage of the first anodizing treatment is 7 to 12 V, the voltage holding time is 3 to 8 min, and the voltage increasing rate is 1 to 6 V / min.

8. The method according to any one of claims 1 to 7, characterized in that: The voltage of the second anodizing treatment is 18 to 23 V, the voltage holding time is 30 to 80 min, and the voltage increasing rate is 1 to 6 V / min.

9. The method according to any one of claims 1 to 8, characterized in that: After the second anodizing treatment, the aluminum alloy vacuum valve is sealed.

10. The method according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: (1) a pneumatically driven vacuum valve made of 6082 aluminum alloy is subjected to a degreasing treatment for 10 to 15 minutes; the degreasing liquid used in the degreasing treatment is a nitric acid solution with a concentration of 110 to 150 g / L; and a first water washing is performed after the degreasing treatment is completed; (2) using a sodium hydroxide solution with a concentration of 40 to 90 g / L for 2 to 7 minutes, and then performing a second water wash; (3) using a nitric acid solution with a concentration of 100 to 150 g / L for pickling for 1 to 6 minutes, and then performing a third water wash after the pickling; (4) using a sulfuric acid solution with a concentration of 150 to 200 g / L for a first anodizing treatment; the voltage of the first anodizing treatment is 7 to 12 V, the holding time is 3 to 8 min, and the voltage increase rate is 1 to 6 V / min; (5) After a second anodizing treatment is performed using a sulfuric acid solution with a concentration of 150 to 200 g / L, the aluminum alloy vacuum valve is sealed to obtain an aluminum alloy vacuum valve with an oxide film on the surface; The voltage of the second anodizing treatment is 18 to 23 V, the holding time is 30 to 80 min, and the voltage increase rate is 1 to 6 V / min; The thickness of the oxide film is 16-20 mm; the aluminum alloy vacuum valve with the oxide film on the surface has a withstand voltage of 0.59-0.74 KV and an impedance of 38.57-48.22 KΩ.

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