CN115110125B - A corrosion-resistant super-hydrophobic composite material containing nano Y2O3 particles and a preparation method thereof - Google Patents

Abstract

The invention discloses a kind of corrosion-resistant super-hydrophobic composite material containing nano _{Y2O3 particles} and its preparation method, and the preparation includes the following process: using X100 steel substrate as cathode and pure nickel plate as anode, using Ni-Co- _{Y2O3 electrodeposition} solution for electrodeposition, and obtaining Ni-Co- _{Y2O3 nano} -composite coating with papillary protrusions on the surface of steel substrate; then using low surface energy modification method to make the Ni-Co- _{Y2O3 nano} -composite coating have super-hydrophobicity, and finally drying treatment is carried out to obtain the corrosion-resistant super- _hydrophobic composite material containing nano _Y2O3 particles. The present invention can significantly improve the corrosion resistance of Ni-Co coating, has higher hydrophobicity, and the surface of the obtained coating has micro-nano papillary protrusion structure. When corrosive medium contacts it, the double protection of surface super-hydrophobic film and nano-composite coating hinders corrosive ions from immersing inside the coating, and then improves the corrosion resistance of the coating, and provides new ideas for the novel composite coating prepared to be widely used in soil corrosion environment.

Description

A corrosion-resistant super-hydrophobic composite material containing nano Y2O3 particles and a preparation method thereof

Technical Field

The invention belongs to the technical field of metal surface treatment and modification, and particularly relates to a corrosion-resistant super- _hydrophobic composite material containing nano _Y2O3 particles and a preparation method thereof.

Background technique

Pipeline transportation is currently the main mode of transportation in the oil and gas industry. During the development and transportation of oil and gas, pipeline steel has been in service for a long time in different soil media, such as acidic soil, saline-alkali soil, etc. The soil environment contains a large amount of aqueous mixtures. The large surface energy of pipeline steel makes it easy for water droplets to spread on its surface, increasing the contact area between water (or corrosive substances) and its surface, thereby increasing the occurrence of corrosion. Soil corrosion has become the main reason for threatening the safe operation of oil and gas and causing pipeline corrosion perforation. Nickel-cobalt (Ni-Co) alloy coating has high corrosion resistance, hardness and good wear resistance, and has become the mainstream material for surface coating, but it still cannot meet the existing harsh soil corrosion environment.

Super hydrophobic surface refers to a water contact angle greater than 150° and a rolling angle less than 10°. In general, super hydrophobic surface can be achieved by combining micro-nanostructure and surface modification of low surface energy materials. Low surface energy materials often require fluorosilanes to reduce surface energy, but these substances are expensive, pollute the environment, and are harmful to the human body. How to prepare super hydrophobic Ni-Co alloy coatings without using fluorine-containing materials is a technical problem that needs to be solved in this field.

Summary of the invention

The purpose of the present invention is to provide a corrosion-resistant super-hydrophobic composite material containing nano _Y2O3 particles and a preparation method thereof in view of the problem that the existing Ni-Co alloy coating still cannot meet the needs of modernization under harsh working conditions. The present invention adds second-phase nanoparticles _Y2O3 to the existing Ni-Co coating to strengthen the corrosion resistance of the Ni-Co coating, _and adopts low surface energy modification technology to give the Ni-Co _coating super-hydrophobicity, so as to obtain a super-hydrophobic composite coating with good hydrophobic performance and excellent corrosion resistance, so that the composite material with the super-hydrophobic composite coating is widely used in soil corrosion environment.

The technical solution adopted by the present invention is as follows:

A method for preparing a corrosion-resistant super-hydrophobic composite material containing nano _{Y2O3 particles} comprises the following steps:

A steel substrate is used as a cathode and a pure nickel plate is used as an anode. A Ni-Co- _{Y2O3 electrodeposition} solution is used to perform electrodeposition on the surface of the steel substrate to obtain a Ni-Co- _Y2O3 nanocomposite coating with papillary protrusions. A low surface energy modification method is then used to make the Ni-Co- _{Y2O3 nanocomposite} coating have super-hydrophobicity _. Finally, a drying treatment is performed to obtain the corrosion-resistant super _- hydrophobic composite material containing nano _Y2O3 particles.

Preferably, the composition of the Ni-Co- _{Y2O3 electrodeposition} solution is as follows:

The concentration of NiSO ₄ ·6H ₂ O is 150-300g/L; the concentration of CoSO ₄ ·7H ₂ O is 10-25g/L; the concentration of NiCl ₂ ·6H ₂ O is 15-30g/L; the concentration of H ₃ BO ₃ is 15-30g/L; the concentration of citric acid is 60-90g/L; the concentration of saccharin sodium is 0.5-1g/L; the concentration of sodium dodecylbenzene sulfonate is 0.05-0.10g/L; the concentration of 1,4-butynediol is 0.3-0.6g/L; the concentration of thiourea is 0.01-0.04g/L; the concentration of nano Y ₂ O ₃ is 5-20g/L.

Preferably, the Ni-Co- _{Y2O3 electrodeposition} solution is prepared by mixing a Ni-Co alloy electrodeposition solution and a _{nano Y2O3} dispersion, and the Ni-Co alloy electrodeposition solution is prepared by mixing and dissolving nickel sulfate, cobalt sulfate, boric acid, nickel chloride, citric acid, sodium saccharin, sodium dodecylbenzene sulfonate, 1,4-butynediol, thiourea and deionized water.

Preferably, the preparation process of the nano _{Y2O3 dispersion} includes: adding nano _{Y2O3 particles} to deionized water for ultrasonic dispersion for 15-30 minutes and standing for wetting for 21-24 hours to obtain a nano _{Y2O3 particle} suspension, and then ultrasonically dispersing the _{nano Y2O3} particle suspension again for 20-35 minutes to obtain a nano _{Y2O3 dispersion} .

Preferably, the preparation process of the Ni-Co alloy electrodeposition solution comprises:

Mix NiSO ₄ ·6H ₂ O, CoSO ₄ ·7H ₂ O and NiCl ₂ ·6H ₂ O with deionized water, stir thoroughly to dissolve, and obtain a main salt solution;

Mix H ₃ BO ₃ and deionized water, heat until boiling, and maintain for 5 to 8 minutes to obtain H ₃ BO ₃ solution;

Adding the H ₃ BO ₃ solution dropwise into the main salt solution to obtain solution A;

Mix citric acid, sodium saccharin, sodium dodecylbenzene sulfonate, 1,4-butynediol, thiourea and deionized water, stir and dissolve to obtain solution B;

The solution B is added into the solution A to obtain the Ni—Co alloy electrodeposition solution.

Preferably, the pretreated steel substrate is used for electrodeposition, and the pretreatment process of the steel substrate includes grinding, cleaning, activation and water washing, wherein the grinding process removes the oxide layer on the surface of the steel substrate, the cleaning process removes the oil stains on the surface of the steel substrate, the activation uses dilute hydrochloric acid, and the deionized water is used for rinsing.

Preferably, the cleaning process uses alkaline solution to remove oil, the alkaline solution contains 30-45g/LNaOH, 20-35g/LNa ₃ PO ₄ , 10-25g/LNa ₂ CO ₃ ; the degreasing process is carried out at room temperature, and the degreasing time is 10-25min; the mass fraction of dilute hydrochloric acid during activation is 8%-11%.

Preferably, when the low surface energy modification method is used to make the Ni-Co-Y ₂ O ₃ nanocomposite coating have superhydrophobicity, the low surface energy modification solution used is an ethanol solution of stearic acid, the mass fraction of stearic acid is 1% to 4%, and the low surface energy modification time is 60 to 90 minutes;

When the drying process is performed, the drying temperature is 80 to 110° C. and the drying time is 90 to 120 minutes.

Preferably, during the electrodeposition process, the deposition time is 90-120 min, the distance between the cathode and the anode is 3-4.5 cm, the area ratio of the cathode and the anode is (1:3)-(1:6), the temperature is 45-60°C, the current density is 4-7 A/dm ² , the electrodeposition solution is continuously stirred, and the rotation speed is controlled to be 400-550 rpm.

The present invention also provides a corrosion-resistant super-hydrophobic composite material containing nano Y ₂ O ₃ particles. The composite material is prepared by the preparation method of the present invention as described above.

The present invention has the following beneficial effects:

The present invention contains a method for preparing a corrosion-resistant super-hydrophobic composite material containing nano _{Y2O3 particles} . By adopting direct current electrodeposition, combined with a composite electrodeposition method using _{nano Y2O3} particles as second phase particles and Ni and Co as main elements of a coating, a Ni-Co- _{Y2O3 nano} -composite coating with micro-nano papillary protrusions is prepared. With the help of rare earth _{Y2O3 nano} -particles, hot brittleness can be eliminated, grains can be refined, the hardness and other properties of the coating can be improved, and defects such as micropores on the coating surface can be reduced, thereby improving the corrosion resistance of the coating. The Ni-Co- _{Y2O3 composite} coating is then modified with low surface energy to obtain a Ni-Co- _Y2O3 corrosion-resistant super _- hydrophobic composite coating. The present invention can significantly improve the corrosion resistance of the Ni-Co alloy coating. When the corrosive medium reaches the coating surface, due to the dual protection of the surface hydrophobic layer and the nano-composite coating, it is difficult for corrosive ions to immerse inside, thereby improving the corrosion resistance of the coating, and providing a new idea for preparing a novel metal composite coating. The preparation method of the invention is simple, efficient, easy to control, has mild reaction conditions, and can realize large-scale preparation.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 (a) is a surface morphology of the composite material of the Ni-Co- _Y2O3 corrosion-resistant super-hydrophobic composite coating containing nano- _{Y2O3 particles} prepared in Example 1 of the present invention; Figure 1 (b) is a schematic diagram of the static water contact angle on the surface of the Ni-Co- _Y2O3 super _- hydrophobic composite coating containing nano _{- Y2O3 particles} prepared in Example 1 of the present invention.

Figure 2 (a) is a surface morphology of the composite material of the Ni-Co- _Y2O3 corrosion-resistant super- _hydrophobic composite coating containing nano- _{Y2O3 particles} prepared in Example 2 of the present invention; Figure 2 (b) is a schematic diagram of the static water contact angle of the surface of the Ni-Co- _Y2O3 super _- hydrophobic composite coating containing nano- _{Y2O3 particles} prepared in Example 2 of the present invention.

Figure 3 (a) is a surface morphology of the Ni-Co- _Y2O3 corrosion-resistant super-hydrophobic composite coating containing nano- _{Y2O3 particles} prepared in Example 3 of the present invention; Figure 3 (b) is a schematic diagram of the static water contact angle on the surface of the Ni-Co- _{Y2O3 super -} hydrophobic composite coating containing nano- _{Y2O3 particles} prepared in Example 3 of the present invention.

Figure 4 (a) is a surface morphology of the Ni-Co- _Y2O3 corrosion-resistant super-hydrophobic composite coating containing nano- _{Y2O3 particles} prepared in Example 4 of the present invention; Figure 4 (b) is a schematic diagram of the static water contact angle on the surface of the Ni-Co- _{Y2O3 super -} hydrophobic composite coating containing nano- _{Y2O3 particles} prepared in Example 4 of the present invention.

5 is an AC impedance diagram of the Ni-Co-Y ₂ O ₃ corrosion-resistant super-hydrophobic composite coating containing nano Y ₂ O ₃ particles prepared by X100 steel, Example 1, Example 2, Example 3, and Example 4 of the present invention.

Detailed ways

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

The present invention aims at the disadvantage of low corrosion resistance of Ni-Co coating in the prior art, and uses the rare earth _{nano Y2O3} to fill the defects such as micropores on the surface of the alloy coating, refine the grains, etc. At the same time, the super hydrophobic property effectively reduces the contact area between the substrate and the corrosive medium, and provides multiple protection for the substrate, thereby improving the corrosion resistance of the composite coating. The specific scheme of the present invention is as follows:

The preparation method of the corrosion-resistant super-hydrophobic composite material containing nano _{Y2O3 particles} of the present invention comprises the following steps:

A substrate (such as a pipeline steel substrate) is used as a cathode, a pure nickel plate is used as an anode, and a Ni-Co-Y ₂ O ₃ electrodeposition solution is used for electrodeposition to prepare a Ni-Co-Y ₂ O ₃ composite coating with papillary protrusions on the surface of the substrate; then, a low surface energy material modification method is used to impart superhydrophobicity to the Ni-Co-Y ₂ O ₃ composite coating, and finally a drying treatment is performed to obtain a corrosion-resistant superhydrophobic composite material containing nano Y ₂ O ₃ particles.

Specifically, the Ni-Co-Y ₂ O ₃ electrodeposition solution used in the present invention is a mixture of a Ni-Co alloy electrodeposition solution and a nano Y ₂ O ₃ dispersion. The Ni-Co alloy electrodeposition solution is prepared by fully stirring and dissolving nickel sulfate, cobalt sulfate, boric acid, nickel chloride, citric acid, sodium saccharin, sodium dodecylbenzene sulfonate, 1,4-butynediol, thiourea and deionized water. The concentrations of the components in the Ni-Co-Y ₂ O ₃ electrodeposition solution are as follows: the concentration of NiSO ₄ ·6H ₂ O is 150-300 g/L; the concentration of CoSO ₄ ·7H ₂ O is 10-25 g/L; the concentration of NiCl ₂ ·6H ₂ O is 15-30 g/L; the concentration of H ₃ BO ₃ is 15-30 g/L; the concentration of citric acid is 60-90 g/L; the concentration of saccharin sodium is 0.5-1 g/L; the concentration of SDBS is 0.05-0.10 g/L; the concentration of 1,4-butynediol is 0.3-0.6 g/L; the concentration of thiourea is 0.01-0.04 g/L; and the concentration of nano Y ₂ O ₃ is 5-20 g/L. Nickel sulfate (NiSO ₄ ·6H ₂ O) provides nickel ions for the electrodeposition process; cobalt sulfate (CoSO ₄ ·6H ₂ O) provides cobalt ions for the electrodeposition process; nickel chloride (NiCl ₂ ·6H ₂ O) can prevent anode passivation; boric acid (H ₃ BO ₃ ) is a pH buffer to maintain the stability of the pH value of the plating solution; citric acid (Citric Acid) is a complexing agent to ensure the smooth progress of the electrodeposition reaction process; sodium dodecylbenzene sulfonate (SDBS) is a surfactant to increase the suspension amount of nano Y ₂ O ₃ particles in the plating solution; 1,4-butynediol and sodium saccharin (Sodium Saccharin) play the role of brighteners of the solution, and their main purpose is to make the surface of the formed coating smooth and the grains small during the electrodeposition process.

When preparing the Ni-Co alloy electrodeposition solution, the steps include:

1) Weigh 75-150g NiSO ₄ ·6H ₂ O, 5-12.5g CoSO ₄ ·7H ₂ O and 7.5-15g NiCl ₂ ·6H ₂ O into a 500ml beaker, then add 300ml deionized water, stir thoroughly to dissolve, and prepare the main salt solution;

2) Weigh 7.5-15g _{H 3} BO ₃ , put it into a 100ml beaker, add 50ml deionized water, heat until boiling, maintain for 5-8min, and obtain H ₃ BO ₃ solution;

3) Slowly add H ₃ BO ₃ solution to the main salt solution;

4) Weigh 30-45g citric acid, 0.25-0.5g saccharin sodium, 0.025-0.05g sodium dodecylbenzene sulfonate, 0.15-0.3g 1,4-butynediol and 0.005-0.02g thiourea into a 100ml beaker, add 75ml deionized water, and stir to dissolve;

5) Slowly adding the solution prepared in step 4) into the solution obtained in step 3) to finally obtain a Ni-Co alloy electrodeposition solution.

The nano _{Y2O3 dispersion} is prepared by ultrasonically dispersing nano _{Y2O3 particles} in an appropriate amount of deionized water for 15-30 minutes and standing to wet for 21-24 hours, then ultrasonically dispersing the wetted nano _{Y2O3 particle} suspension again for 20-35 minutes, and finally adding the nano particle dispersion into the prepared Ni-Co alloy electrodeposition solution to obtain a Ni-Co- _{Y2O3 electrodeposition} solution, which is fixed to volume, fully stirred and set aside.

When the Ni-Co-Y ₂ O ₃ nanocomposite coating with papillary protrusions is subjected to low surface energy modification, the low surface energy modification solution used is an ethanol solution of stearic acid, the mass fraction of stearic acid is 1% to 4%, and the low surface energy modification time is 60 to 90 minutes. The Ni-Co-Y ₂ O ₃ super-hydrophobic nanocomposite coating after low surface energy modification is subjected to drying treatment, the drying temperature is 80 to 110° C., and the drying time is 90 to 120 minutes.

During the electrodeposition process, the deposition time is 90 to 120 minutes, the distance between the cathode and cathode is 3 to 4.5 cm, the area ratio of the cathode and cathode is (1:3) to (1:6), the temperature is 45 to 60°C, the current density is 4 to 7 A/dm ² , the electrodeposition solution is continuously stirred, and the rotation speed is controlled at 400 to 550 rpm.

In the technical solution of the present invention, the above-mentioned electrodeposition process is carried out using a pretreated substrate, and the pretreatment process of the substrate includes grinding, cleaning, activation and water washing. Among them, grinding adopts mechanical grinding, which is sandpaper grinding and polishing, cleaning uses ultrasonic alkali liquid degreasing and hot water washing, activation uses dilute hydrochloric acid activation, and then deionized water washing is carried out. In the alkali liquid degreasing process, the alkali liquid formula is 30-45g/LNaOH, 20-35g/LNa ₃ PO ₄ , 10-25g/LNa ₂ CO ₃ ; the degreasing process is carried out at room temperature, and the degreasing time is 10-25min; the mass fraction of dilute hydrochloric acid during activation is 8% to 11%.

The present invention uses the intrinsic hydrophobicity of rare earth _{nano Y2O3} to fill the micropores on the surface of the alloy coating, refine the grains, reduce hydrogen embrittlement and pinholes; at the same time, the super hydrophobic property effectively reduces the contact area between the substrate and the corrosive medium, and provides multiple protections for the substrate, thereby improving the corrosion resistance of the composite coating. Therefore, the corrosion-resistant super hydrophobic composite material containing nano _{Y2O3 particles} of the present invention has excellent corrosion resistance and hydrophobicity.

Embodiment 1:

The preparation method of the corrosion-resistant super-hydrophobic composite material containing nano Y ₂ O ₃ particles in this embodiment uses an X100 steel substrate, and the steps are as follows:

(1) Pretreatment of substrate:

a. Sample packaging: Cut the substrate into a 10mm*10mm*3mm cube, weld one end of the wire to the sample, and package it with epoxy resin to make a working electrode with a working area of ^1cm2 .

b. Mechanical grinding: Use 180#, 400#, 600#, 800#, 1200#, and 1500# sandpaper to grind and polish the working surface of the substrate in turn to remove the oxide layer of the X100 steel substrate; then clean it with acetone and ethanol, blow dry it, and set aside.

c. Alkaline solution degreasing: The degreasing solution used is composed of 30 g/L NaOH, 20 g/L Na ₃ PO ₄ , and 10 g/L Na ₂ CO ₃ ; the degreasing process is carried out in ultrasound at a temperature of 25° C. and the degreasing time is 10 min.

d. Activation: The activation solution is 8% by mass of dilute hydrochloric acid, and the activation time is 1 min.

After each process is completed, it is ultrasonically cleaned with deionized water and blown dry for later use.

(2) Preparation of Ni-Co electrodeposition solution:

Use an electronic balance to weigh 75g of nickel sulfate ( _NiSO4 · _6H2O ), 5g of cobalt sulfate (CoSO4 _{· 6H2O} ), 7.5g of nickel chloride ( _NiCl2 · _6H2O ), 7.5g of boric acid ( _H3BO3 ), 30g of citric acid, _0.25g of sodium saccharin, 0.15g of 1,4-butynediol, 0.005g of thiourea and 0.025g of sodium dodecylbenzene sulfonate (SDBS), and slowly add them into a beaker filled with an appropriate amount of deionized water. After stirring evenly, a Ni-Co alloy electrodeposition solution is obtained for standby use. Use an electronic balance to weigh _2.5g of _Y2O3 particles with a particle size not exceeding 40nm, put them into an appropriate amount of deionized water for ultrasonic dispersion for 15min and let them stand for 21h, then ultrasonically disperse the wetted nanoparticle suspension again for 20min, and finally add the dispersed nanoparticle suspension to the prepared Ni-Co alloy electrodeposition solution to obtain a Ni-Co- _{Y2O3 electrodeposition} solution, dilute to 500mL, and let it stand for use.

(3) Electrodeposition

During the electrodeposition, the positive electrode of the power supply was connected to the pure nickel plate, the negative electrode was connected to the X100 steel substrate, the distance between the positive and negative electrodes was 3 cm, and the current density was set to 4A/ ^dm2 ; the Ni-Co electrodeposition solution in the beaker was heated in a constant temperature water bath, the electrodeposition time was set to 90min, the temperature was 45°C; the mechanical stirring speed was 400rpm. The surface of the sample after electrodeposition was rinsed with deionized water.

(4) Low surface energy modification:

A low surface energy modification solution of 1% stearic acid and 99% anhydrous ethanol was prepared, stirred evenly and set aside. The X100 steel substrate with a certain micro-nano rough structure coating on the surface after electrodeposition was immersed in the stearic acid ethanol solution for 60 minutes.

(5) Drying

The X100 steel substrate modified with low surface energy was dried and placed in an oven at 80°C for 90 minutes. Finally, the X100 steel substrate was packaged in a sample bag and placed in a drying oven for subsequent performance tests.

The surface morphology of the composite material of the Ni-Co-Y ₂ O ₃ corrosion-resistant super-hydrophobic composite coating containing nano Y ₂ O ₃ particles prepared in this example is shown in FIG. 1( a ), and the papillary protrusions on the surface of the coating are substantially uniform.

Embodiment 2:

The preparation method of the corrosion-resistant super-hydrophobic composite material containing nano Y ₂ O ₃ particles in this embodiment uses an X100 steel substrate, and the steps are as follows:

(1) Pretreatment of substrate:

a. Sample packaging: Cut the substrate into a 10mm*10mm*3mm cube, weld one end of the wire to the sample, and package it with epoxy resin to make a working electrode with a working area of ^1cm2 .

b. Mechanical grinding: Use 180#, 400#, 600#, 800#, 1200#, and 1500# sandpaper to grind and polish the working surface of the substrate in turn to remove the oxide layer of the X100 steel substrate; then clean it with acetone and ethanol, blow dry it, and set aside.

c. Alkaline solution degreasing: The degreasing solution used is composed of 35 g/L NaOH, 25 g/L Na ₃ PO ₄ , and 15 g/L Na ₂ CO ₃ ; the degreasing process is carried out in ultrasound at a temperature of 25° C. and the degreasing time is 15 min.

d. Activation: The activation solution is 9% dilute hydrochloric acid, and the activation time is 1 min.

After each process is completed, it is ultrasonically cleaned with deionized water and blown dry for later use.

(2) Preparation of Ni-Co- _{Y2O3 electrodeposition} solution:

100 g of nickel sulfate (NiSO ₄ ·6H ₂ O), 7.5 g of cobalt sulfate (CoSO ₄ ·6H ₂ O), 10 g of nickel chloride (NiCl ₂ ·6H ₂ O), 10 g of boric acid (H ₃ BO ₃ ), 35 g of citric acid, 0.3 g of sodium saccharin, 0.20 g of 1,4-butynediol, 0.01 g of thiourea and 0.03 g of sodium dodecylbenzene sulfonate (SDBS) were weighed on an electronic balance and slowly added into a beaker filled with an appropriate amount of deionized water, and stirred evenly to obtain a Ni-Co alloy electrodeposition solution; 5 g of Y ₂ O ₃ particles with a particle size not exceeding 40 nm were weighed on an electronic balance, placed in an appropriate amount of deionized water for ultrasonic dispersion for 20 min and allowed to stand for 22 h, and then the wetted nanoparticle suspension was ultrasonically dispersed again for 25 min, and finally the dispersed nanoparticle suspension was added into the prepared Ni-Co alloy electrodeposition solution to obtain Ni-Co-Y ₂ O ₃ electrodeposition solution, dilute to 500 mL, and let stand for use.

(3) Electrodeposition:

During the electrodeposition, the positive electrode of the power supply was connected to the pure nickel plate, the negative electrode was connected to the X100 steel substrate, the distance between the positive and negative electrodes was 3.5 cm, and the current density was set to 5A/ ^dm2 ; the Ni-Co- _{Y2O3 electrodeposition} solution in the beaker was heated in a constant temperature water bath, the electrodeposition time was set to 100min, the temperature was set to 50℃; the mechanical stirring speed was 450rpm. The surface of the sample after electrodeposition was rinsed with deionized water.

(4) Low surface energy modification:

A low surface energy modification solution of 2% stearic acid and 98% anhydrous ethanol was prepared, stirred evenly and set aside. The X100 steel substrate with a certain micro-nano rough structure coating on the surface after electrodeposition was immersed in the stearic acid ethanol solution for 65 minutes.

(5) Drying treatment:

The X100 steel substrate modified with low surface energy was dried and placed in an oven at 90°C for 100 min. Finally, the X100 steel substrate was packaged in a sample bag and placed in a drying oven for subsequent performance tests.

The surface morphology of the composite material of the Ni-Co- _Y2O3 corrosion-resistant super- _hydrophobic composite coating containing nano _{Y2O3 particles} prepared in this example is shown in FIG2(a). The papillary protrusions are evenly distributed on the coating surface, and the coating is complete and dense.

Embodiment 3:

The preparation method of the corrosion-resistant super-hydrophobic composite material containing nano Y ₂ O ₃ particles in this embodiment uses an X100 steel substrate, and the steps are as follows:

(1) Pretreatment of substrate:

a. Sample packaging: Cut the substrate into a 10mm*10mm*3mm cube, weld one end of the wire to the sample, and package it with epoxy resin to make a working electrode with a working area of ^1cm2 .

b. Mechanical grinding: Use 180#, 400#, 600#, 800#, 1200#, and 1500# sandpaper to grind and polish the working surface of the substrate in turn to remove the oxide layer of the X100 steel substrate; then clean it with acetone and ethanol, blow dry it, and set aside.

c. Alkaline solution degreasing: The degreasing solution used is composed of: 40g/L NaOH, 30g/L Na ₃ PO ₄ , 20g/L Na ₂ CO ₃ ; the degreasing process is carried out in ultrasound at a temperature of 25° C. and the degreasing time is 20 minutes.

d. Activation: The activation solution is 10% by mass of dilute hydrochloric acid, and the activation time is 1 min.

After each process is completed, it is ultrasonically cleaned with deionized water and blown dry for later use.

(2) Preparation of Ni-Co- _{Y2O3 electrodeposition} solution:

125 g of nickel sulfate (NiSO ₄ ·6H ₂ O), 10 g of cobalt sulfate (CoSO ₄ ·6H ₂ O), 12.5 g of nickel chloride (NiCl ₂ ·6H ₂ O), 12.5 g of boric acid (H ₃ BO ₃ ), 40 g of citric acid, 0.4 g of sodium saccharin, 0.25 g of 1,4-butynediol, 0.015 g of thiourea and 0.04 g of sodium dodecylbenzene sulfonate (SDBS) were weighed on an electronic balance and slowly added into a beaker filled with an appropriate amount of deionized water. After stirring evenly, a Ni-Co alloy electrodeposition solution was obtained. 7.5 g of Y ₂ O with a particle size not exceeding 40 nm was weighed on an electronic balance. ₃ particles were placed in an appropriate amount of deionized water for ultrasonic dispersion for 25 min and allowed to stand for 23 h, and then the wetted nanoparticle suspension was ultrasonically dispersed again for 30 min. Finally, the dispersed nanoparticle suspension was added to the prepared Ni-Co alloy electrodeposition solution to obtain a Ni-Co- _{Y2O3 electrodeposition} solution, which was fixed to 500 mL and allowed to stand for use.

(3) Electrodeposition:

During the electrodeposition, the positive electrode of the power supply was connected to the pure nickel plate, the negative electrode was connected to the X100 steel substrate, the distance between the positive and negative electrodes was 4 cm, and the current density was set to 6A/ ^dm2 ; the Ni-Co- _{Y2O3 plating} solution in the beaker was heated in a constant temperature water bath, the electrodeposition time was set to 110min, the temperature was set to 55℃; the mechanical stirring speed was 500rpm. The surface of the sample after electrodeposition was rinsed with deionized water.

(4) Low surface energy modification:

A low surface energy modification solution of 3% stearic acid and 97% anhydrous ethanol was prepared, stirred evenly and set aside. The X100 steel substrate with a certain micro-nano rough structure coating on the surface after electrodeposition was immersed in the stearic acid ethanol solution for 80 minutes.

(5) Drying treatment:

The X100 steel substrate modified with low surface energy was dried and placed in an oven at 100°C for 110 minutes. Finally, the X100 steel substrate was packaged in a sample bag and placed in a drying oven for subsequent performance tests.

The surface morphology of the composite material of the Ni-Co- _Y2O3 corrosion-resistant super- _hydrophobic composite coating containing nano _{Y2O3 particles} prepared in this embodiment is shown in FIG3(a). The coating surface is uniform, flat, dense and the grains are small.

Embodiment 4:

The preparation method of the corrosion-resistant super-hydrophobic composite material containing nano Y ₂ O ₃ particles in this embodiment uses an X100 steel substrate, and the steps are as follows:

(1) Pretreatment of substrate:

a. Sample packaging: Cut the substrate into a 10mm*10mm*3mm cube, weld one end of the wire to the sample, and package it with epoxy resin to make a working electrode with a working area of ^1cm2 .

b. Mechanical grinding: Use 180#, 400#, 600#, 800#, 1200#, and 1500# sandpaper to grind and polish the working surface of the substrate in turn to remove the oxide layer of the X100 steel substrate; then clean it with acetone and ethanol, blow dry it, and set aside.

c. Alkaline solution degreasing: The degreasing solution used is composed of: 45g/L NaOH, 35g/L Na ₃ PO ₄ , 25g/L Na ₂ CO ₃ ; the degreasing process is carried out in ultrasound at a temperature of 25° C. and the degreasing time is 25 minutes.

d. Activation: The activation solution is 11% dilute hydrochloric acid, and the activation time is 1 min.

After each process is completed, it is ultrasonically cleaned with deionized water and blown dry for later use.

(2) Preparation of Ni-Co- _{Y2O3 electrodeposition} solution:

150 g of nickel sulfate (NiSO ₄ ·6H ₂ O), 12.5 g of cobalt sulfate (CoSO ₄ ·6H ₂ O), 15 g of nickel chloride (NiCl ₂ ·6H ₂ O), 15 g of boric acid (H ₃ BO ₃ ), 45 g of citric acid, 0.4 g of sodium saccharin, 0.3 g of 1,4-butynediol, 0.020 g of thiourea and 0.04 g of sodium dodecylbenzene sulfonate (SDBS) were weighed on an electronic balance and slowly added into a beaker filled with an appropriate amount of deionized water. After stirring evenly, a Ni-Co alloy electrodeposition solution was obtained. 10.0 g of Y ₂ O with a particle size not exceeding 40 nm was weighed on an electronic balance. ₃ particles were placed in an appropriate amount of deionized water for ultrasonic dispersion for 30 min and allowed to stand for 24 h, and then the wetted nanoparticle suspension was ultrasonically dispersed again for 35 min. Finally, the dispersed nanoparticle suspension was added to the prepared Ni-Co alloy electrodeposition solution to obtain a Ni-Co- _{Y2O3 electrodeposition} solution, which was fixed to 500 mL and allowed to stand for use.

(3) Electrodeposition:

During the electrodeposition, the positive electrode of the power supply was connected to the pure nickel plate, the negative electrode was connected to the X100 steel substrate, the distance between the positive and negative electrodes was 4.5 cm, and the current density was set to 7A/ ^dm2 ; the Ni-Co- _{Y2O3 plating} solution in the beaker was heated in a constant temperature water bath, the electrodeposition time was set to 120min, the temperature was set to 60℃; the mechanical stirring speed was 550rpm. The surface of the sample after electrodeposition was rinsed with deionized water.

(4) Low surface energy modification:

A low surface energy modification solution of 4% stearic acid and 96% anhydrous ethanol was prepared, stirred evenly and set aside. The X100 steel substrate with a certain micro-nano rough structure coating on the surface after electrodeposition was immersed in the stearic acid ethanol solution for 90 minutes.

(5) Drying treatment:

The X100 steel substrate modified with low surface energy was dried and placed in an oven at 110°C for 120 min. Finally, the X100 steel substrate was packaged in a sample bag and placed in a drying oven for subsequent performance tests.

The surface morphology of the composite material of the Ni-Co- _Y2O3 corrosion-resistant super- _hydrophobic composite coating containing nano _{Y2O3 particles} prepared in this embodiment is shown in FIG4(a). The coating is uniform and dense, and the papillary protrusions are also evenly distributed.

The contact angle test was performed on the composite materials with Ni-Co-Y ₂ O ₃ corrosion-resistant super-hydrophobic composite coatings prepared in Examples 1 to 4 of the present invention. The results are shown in Table 1:

Table 1

As shown in Table 1, Fig. 1 (b), Fig. 2 (b), Fig. 3 (b) and Fig. 4 (b), the contact angle of the Ni-Co-Y ₂ O ₃ nanocomposite coating prepared on the surface of X100 steel by this method reaches more than 150 °, reaching a super-hydrophobic state. The surface morphology of the Ni-Co-Y ₂ O ₃ super-hydrophobic composite coating prepared on the surface of X100 steel by the embodiment 1 to embodiment 4 of the present invention is characterized, and the results are shown in Fig. 1 (a), Fig. 2 (a), Fig. 3 (a) and Fig. 4 (a), and the mastoid protrusions on the surface of the super-hydrophobic composite coating containing nano Y ₂ O ₃ particles obtained by the embodiment of the present invention are evenly distributed and compact in structure. As shown in Fig. 5, the prepared Ni-Co-Y ₂ O ₃ super-hydrophobic composite coating has excellent corrosion resistance. Due to the dual protective effect of the super-hydrophobic film and the Ni-Co-Y ₂ O ₃ nano-coating on the substrate, the corrosion resistance is significantly improved. On the other hand, the papillary protrusions on the coating surface construct a stable Cassie state, ensuring air capture within the papillary protrusions. The trapped air has a buffering effect, preventing the adsorption of water on the coating surface. In addition, the addition _{of Y2O3} particles has a tendency to fill the defects of the Ni-Co coating; it can also act as a physical barrier, which can significantly prolong the penetration and diffusion of corrosive ions to the substrate surface.

From the above, it can be seen that the present invention can significantly improve the anti-corrosion performance of the Ni-Co coating, has high hydrophobicity, and the surface of the obtained coating has a micro-nano papillary protrusion structure. When the corrosive medium contacts it, the dual protection of the surface super-hydrophobic film and the nano-composite coating prevents the corrosive ions from penetrating into the coating, thereby improving the corrosion resistance of the coating, and providing a new idea for the prepared new composite coating to be widely used in soil corrosion environments.

Claims (8)

1. The preparation method of the corrosion-resistant super-hydrophobic composite material containing nano Y ₂O₃ particles is characterized by comprising the following steps:

The steel matrix is used as a cathode, a pure nickel plate is used as an anode, and Ni-Co-Y ₂O₃ electrodeposition solution is used for electrodeposition on the surface of the steel matrix to obtain a Ni-Co-Y ₂O₃ nano composite coating with mastoid protrusions; then using a low surface energy modification method to enable the Ni-Co-Y ₂O₃ nano composite coating to have superhydrophobicity, and finally drying to obtain the corrosion-resistant superhydrophobic composite material containing nano Y ₂O₃ particles;

The composition of the Ni-Co-Y ₂O₃ electrodeposition solution is as follows:

The concentration of NiSO ₄·6H₂ O is 150-300 g/L; the concentration of CoSO ₄·7H₂ O is 10-25 g/L; the concentration of NiCl ₂·6H₂ O is 15-30 g/L; the concentration of H ₃BO₃ is 15-30 g/L; the concentration of the citric acid is 60-90 g/L; the concentration of saccharin sodium is 0.5-1g/L; the concentration of the sodium dodecyl benzene sulfonate is 0.05-0.10 g/L; the concentration of the 1, 4-butynediol is 0.3-0.6g/L; the concentration of thiourea is 0.01-0.04g/L; the concentration of the nanometer Y ₂O₃ is 5-20g/L;

In the electrodeposition process, the deposition time is 90-120 min, the distance between the cathode and the anode is 3-4.5 cm, the area ratio of the cathode to the anode is (1:3) - (1:6), the temperature is 45-60 ℃, the current density is 4-7A/dm ², the electrodeposition solution is continuously stirred, and the rotating speed is controlled to be 400-550 rpm.

2. The method for preparing the corrosion-resistant super-hydrophobic composite material containing nano Y ₂O₃ particles, which is disclosed in claim 1, is characterized in that the Ni-Co-Y ₂O₃ electrodeposition solution is prepared by mixing a Ni-Co alloy electrodeposition solution and nano Y ₂O₃ dispersion liquid, and the Ni-Co alloy electrodeposition solution is prepared by mixing and dissolving nickel sulfate, cobalt sulfate, boric acid, nickel chloride, citric acid, saccharin sodium, sodium dodecyl benzene sulfonate, 1, 4-butynediol, thiourea and deionized water.

3. The method for preparing the corrosion-resistant super-hydrophobic composite material containing nano Y ₂O₃ particles according to claim 2, wherein the preparation process of the nano Y ₂O₃ dispersion liquid comprises the following steps: adding nano Y ₂O₃ particles into deionized water, performing ultrasonic dispersion for 15-30min, standing and wetting for 21-24h to obtain nano Y ₂O₃ particle suspension, and performing ultrasonic dispersion again on the nano Y ₂O₃ particle suspension for 20-35min to obtain nano Y ₂O₃ dispersion.

4. The method for preparing the corrosion-resistant super-hydrophobic composite material containing nano Y ₂O₃ particles according to claim 2, wherein the preparation process of the Ni-Co alloy electrodeposition solution comprises the following steps:

Mixing NiSO ₄·6H₂O、CoSO₄·7H₂ O and NiCl ₂·6H₂ O with deionized water, and fully stirring for dissolution to obtain a main salt solution;

Mixing H ₃BO₃ with deionized water, heating until boiling, and maintaining for 5-8 min to obtain H ₃BO₃ solution;

dropwise adding the H ₃BO₃ solution into the main salt solution to obtain a solution A;

Mixing citric acid, saccharin sodium, sodium dodecyl benzene sulfonate, 1, 4-butynediol, thiourea and deionized water, and stirring for dissolving to obtain a solution B;

And adding the solution B into the solution A to obtain the Ni-Co alloy electrodeposition solution.

5. The method for preparing the corrosion-resistant super-hydrophobic composite material containing nano Y ₂O₃ particles, which is characterized in that the pre-treated steel matrix is adopted for electrodeposition, the pre-treatment process of the steel matrix comprises polishing, cleaning, activating and washing, wherein the polishing process removes an oxide layer on the surface of the steel matrix, the cleaning process removes greasy dirt on the surface of the steel matrix, the activating is activated by dilute hydrochloric acid, and the washing is performed by deionized water.

6. The method for preparing the corrosion-resistant super-hydrophobic composite material containing nano Y ₂O₃ particles, which is characterized in that alkali liquor is used for degreasing in the cleaning process, wherein the alkali liquor contains 30-45 g/L NaOH and 20-35 g/L Na ₃PO₄、10~25g/L Na₂CO₃; the degreasing process is carried out at room temperature, and the degreasing time is 10-25min; the mass fraction of the dilute hydrochloric acid during activation is 8% -11%.

7. The preparation method of the corrosion-resistant super-hydrophobic composite material containing nano Y ₂O₃ particles, which is characterized in that when the Ni-Co-Y ₂O₃ nano composite coating has super-hydrophobicity by using a low surface energy modification method, the used low surface energy modification solution is ethanol solution of stearic acid, the mass fraction of stearic acid is 1% -4%, and the low surface energy modification time is 60-90 min;

And when the drying treatment is carried out, the drying temperature is 80-110 ℃ and the drying time is 90-120 min.

8. The corrosion-resistant superhydrophobic composite containing nano Y ₂O₃ particles prepared by the method for preparing the corrosion-resistant superhydrophobic composite containing nano Y ₂O₃ particles according to any one of claims 1-7.