CN107556865A - Preparation method of self-repairing anti-corrosion coating on magnesium alloy surface - Google Patents

Abstract

The invention provides a preparation method of a magnesium alloy surface self-repairing anti-corrosion coating. Loading corrosion inhibitor to ZrO with mesoporous structure₂And mixing the carrier with an epoxy resin glue solution, and finally coating the mixed glue solution on the surface of the magnesium alloy substrate, wherein the corrosion inhibitor is one or a plurality of benzotriazole, hexamethylenetetramine, 2-mercaptobenzothiazole or sodium molybdate. ZrO loaded with corrosion inhibitor₂Mixing with epoxy resin glue solution, coating on the surface of a magnesium alloy matrix, and curing at room temperature to obtain the corrosion inhibitor-ZrO₂Epoxy resin coating. The novel coating has the functions of corrosion resistance and self-repairing; the coating is green, environment-friendly, non-toxic and harmless, and has a simple preparation process and lower production cost.

Description

Preparation method of self-repairing anti-corrosion coating on magnesium alloy surface

technical field

The invention relates to a preparation method of a self-repairing anti-corrosion coating on the surface of a magnesium alloy, in particular to a preparation method of a corrosion inhibitor-ZrO ₂ /epoxy resin coating on the surface of a magnesium alloy.

Background technique

Corrosion is due to the electrochemical, chemical and physical effects between the metal material and the surrounding medium, and some changes in the state of the metal, resulting in the destruction of the metal material. In the period after the Industrial Revolution, mechanical equipment was widely used all over the world. Therefore, the phenomenon of corrosion occurred in all fields of production and life. Metal corrosion involves a wide range and causes large economic losses. In some key fields, such as marine petrochemical industry, aerospace, traffic trunk line, etc., it is hoped that the metal equipment used can have a long service life. Once corrosion occurs in certain structures that play a key role, it will cause damage and paralysis of structural equipment, causing serious accidents, causing major economic losses, and even threatening lives. Statistics show that corrosion can cause a loss of about 3% of the gross production value. Traditional magnesium alloys have the advantages of low density, high specific strength, good machinability and castability, and are widely used in transportation, construction and other fields. However, due to the relatively active chemical activity of magnesium itself, magnesium alloys are easy to combine with Oxygen in the air reacts with water, thereby being corroded, and then destroying the material itself, thus affecting the further application of magnesium alloys. Usually, for the characteristics of magnesium alloys that are prone to corrosion, people will build a protective layer on its surface to isolate magnesium alloys from contact with oxygen, water and other corrosive media in the air. However, considering the service life of the protective layer, when it is damaged or fails, the magnesium alloy will be exposed to the surrounding environment and face the risk of being damaged by corrosion.

If the magnesium alloy surface protective layer is repaired regularly, it will be a waste of manpower and material resources. The proposal of self-healing coating has opened up a new way to solve this problem. Self-healing (also called self-healing) means that without the action of external force, when the coating is damaged, the coating sample can fully or partially repair the damaged area, so as to achieve the purpose of delaying corrosion. In the process of preparing coatings, adding corrosion inhibitors is an effective way for coating samples to obtain self-healing function, but directly adding corrosion inhibitors to coating samples will lead to the inactivation of corrosion inhibitors and reduce the coating quality. The stability of the film reduces the corrosion resistance of the coating.

Compared with ordinary nanoparticles, hollow nanoparticles usually exhibit a series of special properties, such as high specific surface area, large pore volume, low density, non-toxicity, etc. At the same time, the corrosion inhibitor is encapsulated in the nano container and then added to the organic coating Among them, the integrity of the coating is greatly improved and the controllable release of the corrosion inhibitor is realized. It is precisely because of these advantages that the application of hollow nanoparticles in the field of anti-corrosion has attracted more and more attention. When the coating containing such nanoparticles loaded with corrosion inhibitors is damaged, changes in some properties of the surrounding environment at the crack (such as pH value, mechanical damage, temperature, potential potential, etc.) will cause changes in the permeability of the surface of the nanocontainer. Change, thereby releasing the corrosion inhibitor, the coating exhibits self-healing characteristics, and plays a slow-release effect on the metal. However, there are reports _on the preparation of ZrO2 mesoporous materials by precipitation method, and the pores are filled with corrosion inhibitors, which are dispersed in epoxy resin glue and coated on the surface of magnesium alloys to achieve coating protection and intelligent release of corrosion inhibitors. Still rare.

Contents of the invention

The purpose of the present invention is to provide a method for preparing a self-repairing anti-corrosion coating on the surface of a magnesium alloy that has both a physical shielding effect and a corrosion inhibitor protection for damage, and provides intelligent protection for the magnesium alloy.

The purpose of the present invention is achieved like this:

_The corrosion inhibitor is loaded into the ZrO2 carrier with a mesoporous structure, then mixed with epoxy resin glue, and finally the mixed glue is coated on the surface of the magnesium alloy substrate, and the corrosion inhibitor is benzotriazole, One or more of hexamethylenetetramine, 2-mercaptobenzothiazole or sodium molybdate.

The present invention may also include:

_1. The ZrO2 carrier with mesoporous structure is prepared by precipitation method, which specifically includes: dissolving _10-13g of ZrOCl2 _· 8H2O solid in 40mL of distilled water to obtain zirconium oxychloride with a concentration of 1.0-1.3mol/L Solution, dissolve 0.13～0.15g cetyltrimethylammonium bromide in 40mL distilled water to obtain a cetyltrimethylammonium bromide solution with a concentration of 0.01～0.02mol/L, and prepare a concentration of 1.0～4.0 mol/L ammonia solution, then mix the zirconium oxychloride solution with the hexadecyltrimethylammonium bromide solution, stir and control the temperature not higher than 50°C, add the ammonia solution dropwise to the zirconium oxychloride and hexadecyltrimethylammonium bromide solution In the mixed solution of alkyltrimethylammonium bromide, add ammonia solution dropwise, heat to 70°C and stir until the precipitation is complete, separate with a centrifuge, dry, roast and grind the precipitation.

_2. The loading of the corrosion inhibitor into the ZrO2 carrier with a mesoporous structure specifically includes: first dissolving the corrosion inhibitor, then adding the ZrO2 carrier with a mesoporous structure to the corrosion inhibitor solution, stirring and impregnating for ₁₂ After 1 hour, the centrifuge separated, and the precipitate was washed with water and dried to obtain ZrO ₂ loaded with corrosion inhibitor.

_3. During the preparation process of the ZrO2 carrier with mesoporous structure, the drying temperature of the precipitate is 110°C, and the drying time is 8-12h; the calcination temperature is 500°C, and the calcination time is 4h.

4. Load the corrosion inhibitor into the ZrO ₂ carrier with a mesoporous structure, and wash the precipitation twice; the drying method of the precipitation is: 60°C, vacuum oven, 4 hours.

5. The amount of ZrO ₂ loaded with corrosion inhibitor is 3-6% of the weight of the resin. After mixing the ZrO ₂ loaded with corrosion inhibitor with the resin, stir for 1 hour; add 651 curing agent, stir for 1 hour; ultrasonically treat for 5 minutes; Let stand for 10min.

6. The number of times of coating the mixed glue solution on the surface of the magnesium alloy substrate is 3 times, and the curing method is: hanging curing; the curing temperature is room temperature; and the curing time is 24-72 hours.

In the process of preparing a coating on the surface of a magnesium alloy substrate, adding a corrosion inhibitor is an effective way for the coating to obtain a self-healing function, but directly adding a corrosion inhibitor to the coating will lead to the inactivation of the corrosion inhibitor and reduce the coating. The stability of the film reduces the corrosion resistance of the coating. The introduction of the hollow nanocapsules of the present invention successfully solves this problem, that is, the corrosion inhibitor is first encapsulated with nanoparticles, and then the encapsulated nanoparticles are added to the resin glue.

The invention provides a method for preparing a magnesium alloy surface corrosion inhibitor-ZrO ₂ /epoxy resin coating, which has both physical shielding effect and corrosion inhibitor protection at the damaged place, and is a kind of anti-corrosion agent that provides intelligent protection for magnesium alloys coating. _The invention provides a new idea of a ZrO2 carrier, using ZrO2, an _oxide with relatively good heat and corrosion resistance, as a carrier, and has lower requirements for equipment and higher purity. The preparation method of the magnesium alloy surface corrosion inhibitor-ZrO ₂ /epoxy resin coating is simple, easy to operate, and reduces the consumption of the corrosion inhibitor and possible pollution to the environment.

In the preparation method of the magnesium alloy surface corrosion inhibitor-ZrO2/epoxy resin coating of the present invention, the zirconia with mesoporous structure is used as a carrier to provide a storage space for the corrosion inhibitor, and the corrosion inhibitor is added to the mesoporous carrier In the process, ZrO ₂ is mixed with epoxy resin after the corrosion inhibitor is loaded, and finally the magnesium alloy substrate is combined with the corrosion inhibitor-ZrO ₂ /epoxy resin self-healing anti-corrosion coating.

The preparation method of magnesium alloy surface corrosion inhibitor-ZrO ₂ /epoxy resin coating provided by the present invention, the preparation steps are: preparation of mesoporous zirconia carrier→corrosion inhibitor filling package→corrosion inhibitor-ZrO ₂ and Epoxy resin glue solution mixing→magnesium alloy matrix is combined with corrosion inhibitor-ZrO ₂ /epoxy resin glue solution and cured. The specific process is as follows:

The first step, the preparation of mesoporous zirconia: respectively prepare a certain concentration of zirconium oxychloride solution, ammonia solution, cetyltrimethylammonium bromide (CTAB) solution; mix a certain volume of CTAB solution and zirconium oxychloride solution Mix; when the solution is evenly mixed, then add a certain volume of ammonia solution drop by drop into the CTAB and zirconium oxychloride solution through a constant pressure dropping funnel; while stirring continuously, white flocculent precipitates will appear in the solution, completely precipitated Finally, the precipitate is separated with a centrifuge; the precipitate is dried, roasted, and ground to obtain a ZrO carrier for use _;

The second step is filling and encapsulation of the corrosion inhibitor: first dissolve the corrosion inhibitor separately; then add a certain amount of carrier to the corrosion inhibitor solution and stir; after a period of time, use a centrifuge to separate to obtain a precipitate, wash with water, and dry. Obtain the ZrO carrier of load corrosion inhibitor _;

The third step is to mix the zirconia carrier loaded with the corrosion inhibitor and the epoxy resin: weigh the epoxy resin, mix the resin and the solvent in proportion, and stir evenly; the zirconia loaded with the corrosion inhibitor, Stir at high speed and add to the epoxy resin glue, mix evenly, add a certain amount of curing agent, stir until evenly mixed, ultrasonic and stand to remove foam;

The fourth step, the magnesium alloy substrate is combined with the corrosion inhibitor-ZrO ₂ /epoxy resin glue: the surface of the magnesium alloy substrate is subjected to a series of treatments to remove the surface oxide film to expose a fresh substrate; then the corrosion inhibitor-ZrO ₂ /ring Oxygen resin glue is uniformly coated on the surface of the magnesium alloy and cured at room temperature.

The invention successively adopts the precipitation method, the solvent evaporation method, the mechanical stirring method and the coating method to prepare the composite coating with intelligent anticorrosion effect. The prepared mesoporous zirconia support has better adaptability to epoxy resin than the traditional support. At the same time, the porous structure of the zirconia carrier provides enough space for the filling of the corrosion inhibitor, which opens up a new filling method for the corrosion inhibitor. The release of traditional corrosion inhibitors will directly act on them in the corrosive environment, which not only causes a lot of waste of corrosion inhibitors, but also pollutes the environment. The invention combines the corrosion inhibitor and coating protection into one, and the coating can not only provide conventional protection, but also effectively release an appropriate amount of corrosion inhibitor to protect damaged parts at scratches or corrosive media, realizing intelligent protection.

The invention designs a preparation method of a magnesium alloy surface corrosion inhibitor-ZrO ₂ /epoxy resin coating. Firstly, the white powder of nano-scale zirconia with mesoporous structure was prepared by precipitation method of zirconium oxychloride octahydrate in ammonia solution; then the corrosion inhibitor was added into the porous structure by infiltration and solvent evaporation ; After loading the corrosion inhibitor, ZrO ₂ is mixed with epoxy resin; finally, the magnesium alloy substrate is immersed in the mixed solution of ZrO ₂ and epoxy resin after loading the corrosion inhibitor, and then hangs and cures at room temperature. Compared with traditional anti-corrosion coatings, this new type of coating not only has the corrosion-resistant and shielding effect of traditional coatings, but also releases corrosion inhibitors after the coating is damaged by external force, forming a corrosion inhibitor adsorption film on the metal surface, making the metal The substrate is protected again. The mesoporous zirconia carrier in this method is an inorganic non-metallic material with high melting and boiling point, small thermal conductivity, large coefficient of thermal expansion, excellent wear resistance and outstanding corrosion resistance. have better adaptability. Moreover, the method uses zirconium dioxide, an oxide with relatively good heat and corrosion resistance, as a carrier, which has lower requirements for equipment and higher purity. In the present invention, one or more corrosion inhibitors are used for compounding, which has a good anticorrosion effect on magnesium alloys.

Using CHI660C electrochemical workstation, 3.5%wt NaCl solution, the auxiliary electrode is a platinum electrode, and the reference electrode is a calomel electrode. The prepared samples are tested, and the electrochemical impedance is analyzed by equivalent circuit fitting using ZSimpWin software . Corrosion inhibitor-ZrO ₂ /epoxy coating is still active on the second day of immersion, and the coating has self-healing performance after damage. The scheme is novel in method, simple in operation, low in cost and low in energy consumption, and is suitable for practical application and large-scale production.

In summary, the advantages and positive effects of the present invention are:

1. The prepared mesoporous zirconia carrier has better adaptability to the resin than the traditional carrier.

2. The method for preparing the mesoporous zirconia carrier has relatively low equipment requirements and high purity.

3. Propose an anti-corrosion method compounded by one or more corrosion inhibitors.

4. Propose a novel encapsulation method of corrosion inhibitor in mesoporous ZrO ₂ .

5. When the coating is corroded, the coating can provide intelligent repair to the substrate.

6. The method of the present invention is environmentally friendly, simple in process and good in effect.

Description of drawings

Fig. ₁ is ZrO2 _The N of mesoporous material Adsorption and desorption drawings;

Figure 2a _- Figure 2b are the BJH adsorption and desorption pore size distribution diagrams of ZrO2 mesoporous materials. The specific surface area of the ZrO ₂ mesoporous material is 47.465m ² /g, and the single-point average pore radius is 14.48nm.

Fig. 3 is the Bode model diagram of corrosion inhibitor-5% ZrO ₂ /epoxy coating in 3.5% NaCl solution. In the Bode pattern, soaking in 3.5% NaCl solution for 1 day, the impedance modulus value becomes larger, and the corrosion inhibitor-ZrO ₂ /epoxy coating has a certain self-healing effect.

Fig. 4 Bode model diagram of different contents of corrosion inhibitor-ZrO ₂ /epoxy coating in 3.5% NaCl solution.

detailed description

The following examples describe the present invention in more detail.

Example 1

The first step, preparation of mesoporous zirconia support: dissolve 11g ZrOCl ₂ 8H ₂ O solid in 40mL distilled water, the concentration is 1.0mol/L; preparation of CTAB solution: dissolve 0.13g CTAB in 40mL distilled water, CTAB solution with a concentration of 0.01mol/L; prepare ammonia solution with a concentration of 1.0mol/L; then mix zirconium oxychloride with CTAB solution and stir at a temperature not higher than 50°C; pass the prepared ammonia solution through the dropping funnel Add dropwise to the mixed solution of zirconium oxychloride and CTAB; adjust pH=9.5, after adding ammonia solution dropwise, heat to above 70°C, white flocculent precipitate will appear in the solution, after complete precipitation, separate the precipitate with a centrifuge The obtained precipitate was placed in a beaker, dried at 110°C for 10h, ground into powder and then roasted in a muffle furnace at 500°C for 4 hours to obtain a sample for use.

The second step, filling and encapsulating the corrosion inhibitor: Measure 20mL of ethanol solution, add the corrosion inhibitor powder, and place it on a magnetic stirrer to stir continuously until the solution is saturated. Then, weigh ₁ g of ZrO2 carrier, add it to the saturated corrosion inhibitor-ethanol solution, and stir for about 12 hours. Separate with a centrifuge to obtain a precipitate, wash it twice with distilled water, put it into a vacuum oven at 60°C, and dry it for ₄ hours to obtain a ZrO2 carrier loaded with a corrosion inhibitor.

The 3rd step, the mixing of the zirconia carrier of load corrosion inhibitor and epoxy resin: take epoxy resin E44, according to resin/solvent=5/2 (solvent is mixed solvent, n-butanol/xylene=7/ 3) and mix evenly; then according to the amount of resin, weigh 1% zirconia loaded with corrosion inhibitor, stir evenly for 1 hour at high speed, then add curing agent, stir again for 1 hour until evenly mixed, and ultrasonic for 5 minutes And let it stand for 10min.

The fourth step, combining the magnesium alloy substrate with the corrosion inhibitor-ZrO ₂ /: uniformly coat the corrosion inhibitor-ZrO ₂ /epoxy resin glue on the surface of the magnesium alloy, and after repeated coating for 3 times, carry out hanging curing at room temperature for 72 Hour.

Example 2

The first step, preparation of mesoporous zirconia support: dissolve 11g ZrOCl ₂ 8H ₂ O solid in 40mL distilled water, the concentration is 1.0mol/L; preparation of CTAB solution: dissolve 0.13g CTAB in 40mL distilled water, CTAB solution with a concentration of 0.01mol/L; prepare ammonia solution with a concentration of 1.0mol/L; then mix zirconium oxychloride with CTAB solution and stir at a temperature not higher than 50°C; pass the prepared ammonia solution through the dropping funnel Add dropwise to the mixed solution of zirconium oxychloride and CTAB; adjust pH=9.5, after adding ammonia solution dropwise, heat to above 70°C, white flocculent precipitate will appear in the solution, after complete precipitation, separate the precipitate with a centrifuge The obtained precipitate was placed in a beaker, dried at 110°C for 10h, ground into powder and then roasted in a muffle furnace at 500°C for 4 hours to obtain a sample for use.

The second step, filling and encapsulating the corrosion inhibitor: Measure 20mL of ethanol solution, add the corrosion inhibitor powder, and place it on a magnetic stirrer to stir continuously until the solution is saturated. Then, weigh ₁ g of ZrO2 carrier, add it to the saturated corrosion inhibitor-ethanol solution, and stir for about 12 hours. Separate with a centrifuge to obtain a precipitate, wash it twice with distilled water, put it into a vacuum oven at 60°C, and dry it for ₄ hours to obtain a ZrO2 carrier loaded with a corrosion inhibitor.

The 3rd step, the mixing of the zirconia carrier of load corrosion inhibitor and epoxy resin: take epoxy resin E44, according to resin/solvent=5/2 (solvent is mixed solvent, n-butanol/xylene=7/ 3) and mix evenly; then according to the amount of resin, weigh 3% zirconia loaded with corrosion inhibitor, stir at high speed for 1 hour, then add curing agent, stir again for 1 hour until mixed evenly, ultrasonic for 5 minutes And let it stand for 10min.

The fourth step, combining the magnesium alloy substrate with the corrosion inhibitor-ZrO ₂ /: uniformly coat the corrosion inhibitor-ZrO ₂ /epoxy resin glue on the surface of the magnesium alloy, and after repeated coating for 3 times, carry out hanging curing at room temperature for 72 Hour.

Example 3

The first step, preparation of mesoporous zirconia support: dissolve 11g ZrOCl ₂ 8H ₂ O solid in 40mL distilled water, the concentration is 1.0mol/L; preparation of CTAB solution: dissolve 0.13g CTAB in 40mL distilled water, CTAB solution with a concentration of 0.01mol/L; prepare ammonia solution with a concentration of 1.0mol/L; then mix zirconium oxychloride with CTAB solution and stir at a temperature not higher than 50°C; pass the prepared ammonia solution through the dropping funnel Add dropwise to the mixed solution of zirconium oxychloride and CTAB; adjust pH=9.5, after adding ammonia solution dropwise, heat to above 70°C, white flocculent precipitate will appear in the solution, after complete precipitation, separate the precipitate with a centrifuge The obtained precipitate was placed in a beaker, dried at 110°C for 10h, ground into powder and then roasted in a muffle furnace at 500°C for 4 hours to obtain a sample for use.

The second step, filling and encapsulating the corrosion inhibitor: Measure 20mL of ethanol solution, add the corrosion inhibitor powder, and place it on a magnetic stirrer to stir continuously until the solution is saturated. Then, weigh ₁ g of ZrO2 carrier, add it to the saturated corrosion inhibitor-ethanol solution, and stir for about 12 hours. Separate with a centrifuge to obtain a precipitate, wash it twice with distilled water, put it into a vacuum oven at 60°C, and dry it for ₄ hours to obtain a ZrO2 carrier loaded with a corrosion inhibitor.

The 3rd step, the mixing of the zirconia carrier of load corrosion inhibitor and epoxy resin: take epoxy resin E44, according to resin/solvent=5/2 (solvent is mixed solvent, n-butanol/xylene=7/ 3) and mix evenly; then according to the amount of resin, weigh 5% zirconia loaded with corrosion inhibitor, stir evenly at high speed for 1 hour, then add curing agent, stir again for 1 hour until evenly mixed, and ultrasonic for 5 minutes And let it stand for 10min.

The fourth step, combining the magnesium alloy substrate with the corrosion inhibitor-ZrO ₂ /: uniformly coat the corrosion inhibitor-ZrO ₂ /epoxy resin glue on the surface of the magnesium alloy, and after repeated coating for 3 times, carry out hanging curing at room temperature for 72 Hour.

The mesoporous zirconia carrier prepared in the invention is prepared by using CTAB as an active agent, ZrOCl ₂ ·8H ₂ O and ammonia water precipitation. The comparative surface area and pore diameter of the zirconia support were measured by nitrogen adsorption and desorption test (BET) (Fig. 1, Fig. 2a-Fig. 2b). Using CHI660C electrochemical workstation, 3.5%wt NaCl solution, the auxiliary electrode is a platinum electrode, and the reference electrode is a calomel electrode. The prepared samples are tested, and the electrochemical impedance is analyzed by equivalent circuit fitting using ZSimpWin software (Figure 3, Figure 4). The equivalent circuit is simulated by software, and the corrosion behavior of ZrO ₂ epoxy resin self-healing anti-corrosion coatings with different corrosion times and different contents of corrosion inhibitors is compared to study the corrosion behavior.

Above-mentioned specific implementation mode is in order to illustrate the characteristics of the present invention, and implementation case has introduced inventive concept, the time of experimental reaction, temperature and reagent consumption and operating method, but can not limit the claims of the present invention, any other does not deviate from the present invention. The technical solutions of the invention are all included in the protection scope of the present invention.

Claims (7)

1. A preparation method for self-repairing anti _- corrosion coating on magnesium alloy surface is characterized in that: corrosion inhibitor is loaded into the ZrO2 carrier with mesoporous structure, then mixed with epoxy resin glue, and finally mixed glue The corrosion inhibitor is coated on the surface of the magnesium alloy substrate, and the corrosion inhibitor is one or more compounds of benzotriazole, hexamethylenetetramine, 2-mercaptobenzothiazole or sodium molybdate. 2. the preparation method of magnesium alloy surface self-repairing anti-corrosion coating according to claim ₁ , is characterized in that, described ZrO with mesoporous structure Carrier is to adopt precipitation method to prepare, specifically comprises: 10～13g Dissolve the solid ZrOCl ₂ 8H ₂ O in 40mL distilled water to obtain a zirconium oxychloride solution with a concentration of 1.0-1.3mol/L, and dissolve 0.13-0.15g of cetyltrimethylammonium bromide in 40mL of distilled water to obtain a concentration of 0.01～0.02mol/L cetyltrimethylammonium bromide solution, prepare an ammonia solution with a concentration of 1.0～4.0mol/L, and then mix the zirconium oxychloride solution with cetyltrimethylammonium bromide solution Stir after mixing and control the temperature not higher than 50°C, add the ammonia solution dropwise to the mixed solution of zirconium oxychloride and hexadecyltrimethylammonium bromide, heat to 70°C and stir after the ammonia solution is added dropwise After the precipitation is complete, separate it with a centrifuge, dry the precipitate, roast it, and grind it. 3. the preparation method of magnesium alloy surface self-repairing anti-corrosion coating according to claim 2, is characterized in that, described corrosion inhibitor is loaded into the ZrO with mesoporous structure _In the carrier specifically comprises: first corrosion inhibitor Then the ZrO ₂ carrier with mesoporous structure was added to the corrosion inhibitor solution, stirred and immersed for 12 hours, separated by centrifuge, the precipitate was washed with water and dried to obtain ZrO ₂ loaded with corrosion inhibitor. 4. the preparation method of magnesium alloy surface self-repairing anti-corrosion coating according to claim ₃ is characterized in that having the ZrO of mesoporous structure In the preparation process of carrier, the drying treatment temperature of precipitation is 110 ℃, and drying time is 8～12h; the calcination temperature is 500℃, and the calcination time is 4h. 5. the preparation method of magnesium alloy surface self-repairing anti-corrosion coating according to claim 4 is characterized in that corrosion inhibitor is loaded into the ZrO with mesoporous structure _In the carrier, the number of times of washing of precipitation is twice; The drying method is: 60 ℃, vacuum oven, 4 hours. 6. the preparation method of magnesium alloy surface self-repairing anticorrosion coating according to claim 5 is characterized in that being loaded with the ZrO of corrosion inhibitor _The amount is 3～6% of resin weight, will be loaded with corrosion inhibitor After the ZrO ₂ is mixed with the resin, stir for 1h; add 651 curing agent, stir for 1h; ultrasonically treat for 5min; stand still for 10min. 7. the preparation method of magnesium alloy surface self-repairing anti-corrosion coating according to claim 6 is characterized in that the number of times that described mixed glue solution is coated on magnesium alloy substrate surface is 3 times, and curing method is: Hanging curing; curing temperature is room temperature; curing time is 24-72 hours.