CN115627459B - SiO grows on carbon steel surface2Method of coating - Google Patents

Abstract

The invention discloses a method for growing _SiO2 coating on the surface of carbon steel, comprising: step 1, preparing _SiO2 sol; step 2, placing a substrate flat on a beaker containing ethyl orthosilicate, placing the beaker containing the substrate on a heating table to obtain an assembly system, subjecting the assembly system to negative pressure treatment, drying, completing evaporation of ethyl orthosilicate on one side, flipping the substrate, repeating the operation, completing evaporation of ethyl orthosilicate on the other side; step 3, immersing and drying the substrate evaporated with ethyl orthosilicate and then firing, completing the growth of _SiO2 coating on the surface of carbon steel. The method for growing _SiO2 coating on the surface of carbon steel of the invention uses a pulling and dipping method to grow _SiO2 coating on the surface of carbon steel evaporated with ethyl orthosilicate, achieving uniform coating on both sides of the steel plate at one time, the _SiO2 coating has strong bonding with the steel plate, has good spreadability, and can fully utilize the high chemical stability and good corrosion resistance of the _SiO2 coating to achieve corrosion protection of the steel plate.

Description

A method for growing SiO2 coating on carbon steel surface

Technical Field

The invention belongs to the technical field of corrosion prevention, and in particular relates to a method for growing a _SiO2 coating on the surface of carbon steel.

Background technique

In recent years, carbon steel (20 steel) has played an important role in the construction of thermal pipelines. However, since 20 steel is generally exposed to air, such as in moist soil environments, its surface is very easy to react with oxygen, moisture, etc., resulting in rust, which greatly affects the service life of thermal pipelines.

In order to solve the problem of corrosion prevention of thermal pipelines, the current method of adding an organic protective layer is mainly used to achieve the purpose of corrosion prevention of the outer layer of the steel pipe by isolating 20 steel from the outside air or water. However, organic materials have the defect of low strength. During the construction and maintenance of pipelines, protective notch-type corrosion points often appear due to scratches, further accelerating the reduction of steel life. In addition, the structure of pipeline interfaces, valves and other locations is relatively complex, and it is difficult to effectively cover the organic layer, making interfaces and valves and other locations the weak links in the corrosion prevention of thermal pipeline systems. In addition, the corrosion of the inner wall of the steel pipe caused by the operation of the thermal pipeline is often difficult to be effectively taken seriously. Providing an effective method for comprehensive corrosion prevention of 20 steel pipes is one of the main ways to solve the current corrosion of thermal pipelines.

Summary of the invention

The technical problem to be solved by the present invention is to provide a method for growing _SiO2 coating on the surface of carbon steel in view of the shortcomings of the above-mentioned prior art. The method uses a pulling and dipping method to grow SiO2 coating on the surface of carbon steel evaporated with ethyl orthosilicate, so as to achieve a uniform coating on both sides of the steel plate at one time. _{The SiO2 coating} has strong bonding with the steel plate and good spreadability, and can fully utilize the high chemical stability and good corrosion resistance of the _SiO2 coating to achieve corrosion protection of the steel plate.

In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for growing _SiO2 coating on the surface of carbon steel, characterized by comprising:

Step 1: providing _SiO2 sol, specifically comprising:

Step 101, mix tetraethyl orthosilicate and anhydrous ethanol, stir at 25° C. to 40° C. for 1 h to 2 h, add deionized water, and continue stirring for 1 h to 2 h to obtain solution A;

Step 102, adding ammonia water to the solution A until the pH value is 10-11 to obtain a suspension;

Step 103, centrifuging the suspension to obtain particles, washing the particles with ethanol and placing them at room temperature;

Step 104, placing the particles after standing at room temperature in a mixed solution of acetylacetone, anhydrous ethanol and hexane, ultrasonicating at room temperature for 30 minutes to 40 minutes and then stirring for 1 hour to 2 hours to obtain _SiO2 sol;

Step 2: evaporating tetraethyl orthosilicate on the substrate, specifically comprising:

Step 201, grinding, polishing and cleaning the raw steel to obtain a substrate; the raw steel is carbon steel;

Step 202, placing 5 mL to 15 mL of tetraethyl orthosilicate in a clean beaker, placing the substrate described in step 201 flat on the beaker, and placing the beaker with the substrate on a heating table to obtain an assembly system;

Step 203, maintaining the above-mentioned assembly system under a negative pressure condition of -0.28 bar to -0.2 bar for 30 min to 40 min, taking it out, and drying it in an oven at 60° C. to 65° C. for 1 h to 2 h;

Step 204, turning over the substrate, repeating steps 202 and 203, and completing the evaporation of tetraethyl orthosilicate on the other side;

Step 3: growing a _SiO2 coating on the substrate on which tetraethyl orthosilicate is evaporated, specifically comprising:

Step 301, immersing and drying the substrate on which tetraethyl orthosilicate is deposited in step 2 for 5 to 10 times;

Step 302: sinter the immersed and dried material to grow a _SiO2 coating on the surface of the carbon steel.

The above-mentioned method for growing _SiO2 coating on the surface of carbon steel is characterized in that, in step 101, the amount of anhydrous ethanol is 5 to 10 times the amount of tetraethyl orthosilicate.

The above-mentioned method for growing _SiO2 coating on the surface of carbon steel is characterized in that, in step 101, the amount of deionized water is 1 to 2 times the amount of tetraethyl orthosilicate.

The above-mentioned method for growing _SiO2 coating on the surface of carbon steel is characterized in that, in step 102, the mass percentage of the ammonia water is 10% to 25%.

The above-mentioned method for growing _SiO2 coating on the surface of carbon steel is characterized in that, in step 104, in the mixed solution of acetylacetone, anhydrous ethanol and hexane, the amount of acetylacetone is 6 to 10 times the amount of the tetraethyl orthosilicate substance in step 101, the amount of anhydrous ethanol is 5 to 10 times the amount of the tetraethyl orthosilicate substance in step 101; the amount of hexane is 5 to 10 times the amount of the tetraethyl orthosilicate substance in step 101.

The above-mentioned method for growing _SiO2 coating on the surface of carbon steel is characterized in that, in step 202, the temperature of the heating platform is 185°C to 190°C.

The above-mentioned method for growing _SiO2 coating on the surface of carbon steel is characterized in that in step 301, the immersion drying treatment includes: under room temperature conditions, immersing the substrate on which tetraethyl orthosilicate is vapor-deposited in step 2 in the _SiO2 sol described in step 1, maintaining it for 1s to 5s, pulling it away from the _SiO2 sol at a pulling speed of 4mm/s to 5mm/s, and placing the pulled material at 80℃ to 100℃ for drying.

The above-mentioned method for growing _SiO2 coating on the surface of carbon steel is characterized in that, in step 302, the firing temperature is 400°C to 450°C.

Compared with the prior art, the present invention has the following advantages:

1. The method for growing _SiO2 coating on the surface of carbon steel of the present invention utilizes the pulling and dipping method to grow _SiO2 coating on the surface of carbon steel evaporated with ethyl orthosilicate, so as to realize double-sided uniform coating of the steel plate at one time. The _SiO2 coating has strong bonding with the steel plate and good spreadability, and can fully utilize the high chemical stability and good corrosion resistance of the _SiO2 coating to realize corrosion protection of the steel plate.

2. The method of the present invention includes using ethyl orthosilicate to evaporate carbon steel before growing the _SiO2 coating, which can effectively improve the surface tension of the carbon steel and avoid shrinkage of the growing _SiO2 coating.

3. The method of the present invention is simple, easy to operate and suitable for popularization and application.

The technical solution of the present invention is further described in detail below in conjunction with embodiments.

Detailed ways

The _SiO2 coating grown on the surface of carbon steel of the present invention is achieved by growing the _SiO2 coating on a substrate on which tetraethyl orthosilicate is vapor-deposited, wherein the temperature for vapor-depositing the tetraethyl orthosilicate is 185°C to 190°C, the negative pressure is -0.28 bar to -0.2 bar, and the temperature for sintering the _SiO2 sol is 400°C to 450°C, so as to obtain a substrate on which tetraethyl orthosilicate is vapor-deposited with a suitable condensation amount, thereby obtaining a _SiO2 gel film with an effective anti-corrosion effect.

Example 1

This embodiment provides a method for growing a _SiO2 coating on a carbon steel surface, comprising:

Step 1: providing _SiO2 sol, specifically comprising:

Step 101, 1 mol of ethyl orthosilicate and 5 mol of anhydrous ethanol were mixed, stirred at 25° C. for 1 h, 1 mol of deionized water was added, and stirring was continued for 1 h to obtain a solution A;

Step 102, adding ammonia water to the solution A until the pH value is 10, to obtain a suspension, wherein the suspension is white and flocculated; the mass percentage of the ammonia water is 10%;

Step 103, centrifuging the suspension to obtain particles, washing the particles twice with ethanol, and placing the washed particles at room temperature for 2 hours to allow the ethanol to evaporate;

Step 104, placing the particles after standing at room temperature in a mixed solution of acetylacetone, anhydrous ethanol and hexane, ultrasonicating for 30 minutes at room temperature and then stirring for 1 hour to obtain _SiO2 sol; in the mixed solution of acetylacetone, anhydrous ethanol and hexane, the amount of acetylacetone is 6 times the amount of the tetraethyl orthosilicate in step 101, the amount of anhydrous ethanol is 5 times the amount of the tetraethyl orthosilicate in step 101; the amount of hexane is 5 times the amount of the tetraethyl orthosilicate in step 101;

Step 2: Evaporating tetraethyl orthosilicate on a substrate, wherein the substrate is a steel substrate, specifically comprising:

Step 201, grinding, polishing and cleaning a carbon steel having a size of 40 mm×40 mm with 400#, 1500# and 3000# sandpaper in sequence to obtain a substrate; the cleaning is performed with anhydrous ethanol; the carbon steel is 20 steel, and the 20 steel is purchased from Tianjin Zhongtai Huaying Steel;

Step 202, place 5 ml of tetraethyl orthosilicate in a clean beaker, place the substrate described in step 201 flat on the beaker, place the beaker with the substrate on a heating table at a temperature of 185° C., and obtain an assembled system; the capacity of the beaker is 25 ml; the heating table is a JFTOOIS flat heating table;

Step 203, keeping the above-mentioned assembly system under negative pressure of -0.26 bar for 30 minutes, taking it out, and drying it in a 60° C. oven for 1 hour; the negative pressure condition may be placing the assembly system in a stainless steel container, evacuating to negative pressure, and sealing it, and the pump power used for the evacuation is 15W;

Step 204, turning over the substrate, repeating steps 202 and 203, and completing the evaporation of tetraethyl orthosilicate on the other side;

Step 3: growing a _SiO2 coating on the substrate on which tetraethyl orthosilicate is evaporated, specifically comprising:

Step 301, immersing and drying the substrate on which the tetraethyl orthosilicate is deposited in step 2 for 5 times; the immersion drying process comprises: immersing the substrate on which the tetraethyl orthosilicate is deposited in step 2 in the _SiO2 sol in step 1 at room temperature for 3 seconds, pulling the substrate away from the _SiO2 sol at a pulling speed of 4 mm/s, and placing the pulled substrate in a muffle furnace at 80°C for drying for 10 minutes; the room temperature is 20°C to 25°C;

Step 302: Place the immersed dried material in a rapid heat treatment furnace at 400°C and sinter for 10 minutes to grow a _SiO2 coating on the surface of the carbon steel; the sintering heating rate is 120°C/min.

After the waste material of the carbon steel surface with _SiO2 coating grown on the surface of the present embodiment was removed, a hydrochloric acid corrosion performance test was conducted. The test method includes: immersing the carbon steel in 0.1 mol/L dilute hydrochloric acid for 4 hours and observing the surface corrosion marks. The results show that there are no corrosion marks on the surface. The carbon steel with _SiO2 coating grown on the surface obtained by the method of the present invention has a uniform and dense coating, which can effectively wrap the carbon steel plate and has a good anti-corrosion effect.

Example 2

This embodiment provides a method for growing a _SiO2 coating on a carbon steel surface, comprising:

Step 1: providing _SiO2 sol, specifically comprising:

Step 101, 1 mol of ethyl orthosilicate and 10 mol of anhydrous ethanol are mixed, stirred at 40° C. for 2 h, 2 mol of deionized water is added, and stirring is continued for 2 h to obtain a solution A;

Step 102, adding ammonia water to the solution A until the pH value is 11, to obtain a suspension, wherein the suspension is white and flocculated; the mass percentage of the ammonia water is 25%;

Step 103, centrifuging the suspension to obtain particles, washing the particles with ethanol for 4 times, and placing the washed particles at room temperature for 2 hours to allow the ethanol to evaporate;

Step 104, placing the particles after standing at room temperature in a mixed solution of acetylacetone, anhydrous ethanol and hexane, ultrasonicating for 40 minutes at room temperature and then stirring for 2 hours to obtain _SiO2 sol; in the mixed solution of acetylacetone, anhydrous ethanol and hexane, the amount of acetylacetone is 10 times the amount of the tetraethyl orthosilicate in step 101, the amount of anhydrous ethanol is 10 times the amount of the tetraethyl orthosilicate in step 101; the amount of hexane is 10 times the amount of the tetraethyl orthosilicate in step 101;

Step 2: Evaporating tetraethyl orthosilicate on a substrate, wherein the substrate is a steel substrate, specifically comprising:

Step 201, grinding, polishing and cleaning a carbon steel having a size of 40 mm×40 mm with 400#, 1500# and 3000# sandpaper in sequence to obtain a substrate; the cleaning is performed with anhydrous ethanol; the carbon steel is 20 steel, and the 20 steel is purchased from Tianjin Zhongtai Huaying Steel;

Step 202, place 10 ml of tetraethyl orthosilicate in a clean beaker, place the substrate described in step 201 flat on the beaker, place the beaker with the substrate on a heating table at a temperature of 190° C., and obtain an assembly system; the capacity of the beaker is 25 ml; the heating table is a JFTOOIS flat heating table;

Step 203, keeping the above-mentioned assembly system under negative pressure of -0.23 bar for 40 minutes, taking it out, and drying it in a 65° C. oven for 2 hours; the negative pressure condition may be placing the assembly system in a stainless steel container, evacuating to negative pressure, and sealing it, and the pump power used for the evacuation is 15W;

Step 204, turning over the substrate, repeating steps 202 and 203, and completing the evaporation of tetraethyl orthosilicate on the other side;

Step 3: growing a _SiO2 coating on the substrate on which tetraethyl orthosilicate is evaporated, specifically comprising:

Step 301, immersing and drying the substrate on which the tetraethyl orthosilicate is deposited in step 2 for 10 times; the immersion drying process comprises: immersing the substrate on which the tetraethyl orthosilicate is deposited in step 2 in the _SiO2 sol in step 1 at room temperature, holding for 2 seconds, pulling the substrate away from the _SiO2 sol at a pulling speed of 5 mm/s, and placing the pulled substrate in a muffle furnace at 100°C for drying for 10 minutes;

Step 302: Place the immersed dried material in a muffle furnace at 450° C. and sinter for 10 minutes to grow a SiO ₂ coating on the surface of the carbon steel; the heating rate of the sintering is 120° C./min.

The performance of the carbon steel with _SiO2 coating grown on the surface in this embodiment is basically the same as that in embodiment 1.

Example 3

This embodiment provides a method for growing a _SiO2 coating on a carbon steel surface, comprising:

Step 1: providing _SiO2 sol, specifically comprising:

Step 101, 1 mol of ethyl orthosilicate and 7 mol of anhydrous ethanol were mixed, stirred at 30° C. for 2 h, 1 mol of deionized water was added, and stirring was continued for 1 h to obtain a solution A;

Step 102, adding ammonia water to the solution A until the pH value is 10, to obtain a suspension, wherein the suspension is white and flocculated; the mass percentage of the ammonia water is 20%;

Step 103, centrifuging the suspension to obtain particles, washing the particles with ethanol for 3 times, and placing the washed particles at room temperature for 2 hours to allow the ethanol to evaporate;

Step 104, placing the particles after standing at room temperature in a mixed solution of acetylacetone, anhydrous ethanol and hexane, ultrasonicating for 35 minutes at room temperature and then stirring for 2 hours to obtain _SiO2 sol; in the mixed solution of acetylacetone, anhydrous ethanol and hexane, the amount of acetylacetone is 8 times the amount of the tetraethyl orthosilicate in step 101, the amount of anhydrous ethanol is 7 times the amount of the tetraethyl orthosilicate in step 101; the amount of hexane is 10 times the amount of the tetraethyl orthosilicate in step 101;

Step 2: Evaporating tetraethyl orthosilicate on a substrate, wherein the substrate is a steel substrate, specifically comprising:

Step 201, grinding, polishing and cleaning a carbon steel having a size of 40 mm×40 mm with 400#, 1500# and 3000# sandpaper in sequence to obtain a substrate; the cleaning is performed with anhydrous ethanol; the carbon steel is 20 steel, and the 20 steel is purchased from Tianjin Zhongtai Huaying Steel;

Step 202, place 15 ml of tetraethyl orthosilicate in a clean beaker, place the substrate described in step 201 flat on the beaker, place the beaker with the substrate on a heating table at a temperature of 185° C., and obtain an assembled system; the capacity of the beaker is 25 mL; the heating table is a JFTOOIS flat heating table;

Step 203, keeping the above-mentioned assembly system under negative pressure of -0.2 bar for 35 minutes, taking it out, and drying it in a 60° C. oven for 2 hours; the negative pressure condition may be placing the assembly system in a stainless steel container, evacuating to negative pressure, and sealing it, and the pump power used for the evacuation is 15W;

Step 204, turning over the substrate, repeating steps 202 and 203, and completing evaporation of tetraethyl orthosilicate on the other side;

Step 3: growing a _SiO2 coating on the substrate on which tetraethyl orthosilicate is evaporated, specifically comprising:

Step 301, immersing and drying the substrate on which the tetraethyl orthosilicate is deposited in step 2 for 8 times; the immersion drying process comprises: immersing the substrate on which the tetraethyl orthosilicate is deposited in step 2 in the _SiO2 sol in step 1 at room temperature for 1 second, pulling it away from the _SiO2 sol at a pulling speed of 4.5 mm/s, and placing the pulled material in a muffle furnace at 90°C for drying for 10 minutes;

Step 302, placing the immersed dried material in a rapid heat treatment furnace at 420°C for 10 minutes to complete the growth of _SiO2 coating on the surface of the carbon steel; the heating rate of the sintering is 120°C/min;

The performance of the carbon steel with _SiO2 coating grown on the surface in this embodiment is basically the same as that in embodiment 1.

Example 4

This embodiment provides a method for growing a _SiO2 coating on a carbon steel surface, comprising:

Step 1: providing _SiO2 sol, specifically comprising:

Step 101, 1 mol of tetraethyl orthosilicate and 10 mol of anhydrous ethanol were mixed, stirred at 35° C. for 1 h, 1 mol of deionized water was added, and stirring was continued for 2 h to obtain a solution A;

Step 102, adding ammonia water to the solution A until the pH value is 11, to obtain a suspension, wherein the suspension is white and flocculated; the mass percentage of the ammonia water is 12%;

Step 103, centrifuging the suspension to obtain particles, washing the particles twice with ethanol, and placing the washed particles at room temperature for 2 hours to allow the ethanol to evaporate;

Step 104, placing the particles after standing at room temperature in a mixed solution of acetylacetone, anhydrous ethanol and hexane, ultrasonicating for 30 minutes at room temperature and then stirring for 2 hours to obtain _SiO2 sol; in the mixed solution of acetylacetone, anhydrous ethanol and hexane, the amount of acetylacetone is 6 times the amount of the tetraethyl orthosilicate in step 101, the amount of anhydrous ethanol is 10 times the amount of the tetraethyl orthosilicate in step 101; the amount of hexane is 8 times the amount of the tetraethyl orthosilicate in step 101;

Step 2: Evaporating tetraethyl orthosilicate on a substrate, wherein the substrate is a steel substrate, specifically comprising:

Step 201, grinding, polishing and cleaning a carbon steel having a size of 40 mm×40 mm with 400#, 1500# and 3000# sandpaper in sequence to obtain a substrate; the cleaning is performed with anhydrous ethanol; the carbon steel is 20 steel, and the 20 steel is purchased from Tianjin Zhongtai Huaying Steel;

Step 202, place 10 ml of tetraethyl orthosilicate in a clean beaker, place the substrate in step 201 flat on the beaker, place the beaker with the substrate on a heating table at a temperature of 188° C., and obtain an assembly system; the capacity of the beaker is 25 ml; the heating table is a JFTOOIS flat heating table;

Step 203, keeping the above-mentioned assembly system under negative pressure of -0.28 bar for 40 minutes, taking it out, and drying it in a 65° C. oven for 1 hour; the negative pressure condition may be placing the assembly system in a stainless steel container, evacuating to negative pressure, and sealing it, and the pump power used for evacuation is 15W;

Step 204, turning over the substrate, repeating steps 202 and 203, and completing the evaporation of tetraethyl orthosilicate on the other side;

Step 3: growing a _SiO2 coating on the substrate on which tetraethyl orthosilicate is evaporated, specifically comprising:

Step 301, immersing and drying the substrate on which the tetraethyl orthosilicate is deposited in step 2 for 9 times; the immersion drying process comprises: immersing the substrate on which the tetraethyl orthosilicate is deposited in step 2 in the _SiO2 sol in step 1 at room temperature for 5 seconds, pulling the substrate away from the _SiO2 sol at a pulling speed of 5 mm/s, and placing the pulled substrate in a muffle furnace at 80°C for drying for 10 minutes;

Step 302, placing the immersed dried material in a rapid heat treatment furnace at 410°C for 10 minutes to complete the growth of _SiO2 coating on the surface of the carbon steel; the heating rate of the sintering is 120°C/min;

The performance of the carbon steel with _SiO2 coating grown on the surface in this embodiment is basically the same as that in embodiment 1.

Example 5

This embodiment provides a method for growing a _SiO2 coating on a carbon steel surface, comprising:

Step 1: providing _SiO2 sol, specifically comprising:

Step 101, 1 mol of ethyl orthosilicate and 6 mol of anhydrous ethanol are mixed, stirred at 40° C. for 1 h, 2 mol of deionized water are added, and stirring is continued for 2 h to obtain a solution A;

Step 102, adding ammonia water to the solution A until the pH value is 10, to obtain a suspension, wherein the suspension is white and flocculated; the mass percentage of the ammonia water is 25%;

Step 103, centrifuging the suspension to obtain particles, washing the particles with ethanol for 4 times, and placing the washed particles at room temperature for 2 hours to allow the ethanol to evaporate;

Step 104, placing the particles after standing at room temperature in a mixed solution of acetylacetone, anhydrous ethanol and hexane, ultrasonicating for 40 minutes at room temperature and then stirring for 1 hour to obtain _SiO2 sol; in the mixed solution of acetylacetone, anhydrous ethanol and hexane, the amount of acetylacetone is 10 times the amount of the tetraethyl orthosilicate in step 101, the amount of anhydrous ethanol is 6 times the amount of the tetraethyl orthosilicate in step 101; the amount of hexane is 9 times the amount of the tetraethyl orthosilicate in step 101;

Step 2: Evaporating tetraethyl orthosilicate on a substrate, wherein the substrate is a steel substrate, specifically comprising:

Step 201, grinding, polishing and cleaning a carbon steel having a size of 40 mm×40 mm with 400#, 1500# and 3000# sandpaper in sequence to obtain a substrate; the cleaning is performed with anhydrous ethanol; the carbon steel is 20 steel, and the 20 steel is purchased from Tianjin Zhongtai Huaying Steel;

Step 202, place 5 ml of tetraethyl orthosilicate in a clean beaker, place the substrate described in step 201 flat on the beaker, place the beaker with the substrate on a heating table at a temperature of 187° C., and obtain an assembled system; the capacity of the beaker is 25 ml; the heating table is a JFTOOIS flat heating table;

Step 203, keeping the above-mentioned assembly system under negative pressure of -0.25 bar for 30 minutes, taking it out, and drying it in a 60° C. oven for 2 hours; the negative pressure condition may be placing the assembly system in a stainless steel container, evacuating to negative pressure, and sealing it, and the pump power used for the evacuation is 15W;

Step 204, turning over the substrate, repeating steps 202 and 203, and completing the evaporation of tetraethyl orthosilicate on the other side;

Step 3: growing a _SiO2 coating on the substrate on which tetraethyl orthosilicate is evaporated, specifically comprising:

Step 301, immersing and drying the substrate on which the tetraethyl orthosilicate is deposited in step 2 for 5 times; the immersion drying process comprises: immersing the substrate on which the tetraethyl orthosilicate is deposited in step 2 in the _SiO2 sol in step 1 at room temperature for 3 seconds, pulling the substrate away from the _SiO2 sol at a pulling speed of 4 mm/s, and placing the pulled substrate in a muffle furnace at 100°C for drying for 10 minutes;

Step 302, placing the immersed dried material in a rapid heat treatment furnace at 440°C for 10 minutes to complete the growth of _SiO2 coating on the surface of the carbon steel; the heating rate of the sintering is 120°C/min;

The performance of the carbon steel with _SiO2 coating grown on the surface in this embodiment is basically the same as that in embodiment 1.

The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment according to the technical essence of the invention shall still fall within the protection scope of the technical solution of the present invention.

Claims (8)

1. A method for growing _SiO2 coating on the surface of carbon steel, characterized by comprising: Step 1: providing _SiO2 sol, specifically comprising: Step 101, mix tetraethyl orthosilicate and anhydrous ethanol, stir at 25° C. to 40° C. for 1 h to 2 h, add deionized water, and continue stirring for 1 h to 2 h to obtain solution A; Step 102, adding ammonia water to the solution A until the pH value is 10-11 to obtain a suspension; Step 103, centrifuging the suspension to obtain particles, washing the particles with ethanol and placing them at room temperature; Step 104, placing the particles after standing at room temperature in a mixed solution of acetylacetone, anhydrous ethanol and hexane, ultrasonicating at room temperature for 30 minutes to 40 minutes and then stirring for 1 hour to 2 hours to obtain _SiO2 sol; Step 2: evaporating tetraethyl orthosilicate on the substrate, specifically comprising: Step 201, grinding, polishing and cleaning the raw steel to obtain a substrate; the raw steel is carbon steel; Step 202, placing 5 mL to 15 mL of tetraethyl orthosilicate in a clean beaker, placing the substrate described in step 201 flat on the beaker, and placing the beaker with the substrate on a heating table to obtain an assembly system; Step 203, maintaining the above-mentioned assembly system under a negative pressure condition of -0.28 bar to -0.2 bar for 30 min to 40 min, taking it out, and drying it in an oven at 60° C. to 65° C. for 1 h to 2 h; Step 204, turning over the substrate, repeating steps 202 and 203, and completing the evaporation of tetraethyl orthosilicate on the other side; Step 3: growing a _SiO2 coating on the substrate on which tetraethyl orthosilicate is evaporated, specifically comprising: Step 301, immersing and drying the substrate on which tetraethyl orthosilicate is deposited in step 2 for 5 to 10 times; Step 302: sinter the immersed and dried material to grow a _SiO2 coating on the surface of the carbon steel. 2. The method for growing _SiO2 coating on the surface of carbon steel according to claim 1, characterized in that in step 101, the amount of anhydrous ethanol is 5 to 10 times the amount of tetraethyl orthosilicate. 3. The method for growing _SiO2 coating on the surface of carbon steel according to claim 1, characterized in that in step 101, the amount of deionized water is 1 to 2 times the amount of tetraethyl orthosilicate. 4. The method for growing _SiO2 coating on the surface of carbon steel according to claim 1, characterized in that in step 102, the mass percentage of the ammonia water is 10% to 25%. 5. The method for growing _SiO2 coating on the surface of carbon steel according to claim 1, characterized in that, in step 104, in the mixed solution of acetylacetone, anhydrous ethanol and hexane, the amount of acetylacetone is 6 to 10 times the amount of the tetraethyl orthosilicate in step 101, the amount of anhydrous ethanol is 5 to 10 times the amount of the tetraethyl orthosilicate in step 101; the amount of hexane is 5 to 10 times the amount of the tetraethyl orthosilicate in step 101. 6. The method for growing _SiO2 coating on the surface of carbon steel according to claim 1, characterized in that in step 202, the temperature of the heating platform is 185°C to 190°C. 7. A method for growing _SiO2 coating on the surface of carbon steel according to claim 1, characterized in that in step 301, the immersion drying treatment comprises: under room temperature conditions, immersing the substrate on which tetraethyl orthosilicate is vapor-deposited in step 2 in the _SiO2 sol of step 1, maintaining for 1s to 5s, pulling away from the _SiO2 sol at a pulling speed of 4mm/s to 5mm/s, and placing the pulled material at 80℃ to 100℃ for drying. 8. The method for growing _SiO2 coating on the surface of carbon steel according to claim 1, characterized in that in step 302, the firing temperature is 400°C to 450°C.