CN102041509A - Preparation method for constructing super-hydrophobic structure on surface of aluminum alloy - Google Patents

Abstract

The invention discloses a method for preparing the surface of a superhydrophobic aluminum alloy. (1) Firstly, the aluminum alloy plate is mechanically polished and polished to remove surface defects and oxide films, and then cleaned with deionized water; (2) 0.08mol/ L oxalic acid solution and 1mol/L mass concentration of 3.7% hydrochloric acid solution were mixed in a volume ratio of 1:1 and fully stirred to make a mixed acid solution; (3) the aluminum alloy plate was immersed in the mixed acid solution for 12 to 18 hours, and then Take out the aluminum alloy sheet and wash it thoroughly with deionized water, then immerse it in 0.5mol/L potassium permanganate solution for 1-2 hours, then wash it with deionized water, and dry it in a furnace at 80-100°C for 0.5-1.5 hours; (4) Soak in stearic acid ethanol solution with a mass fraction of 1% for 25 to 35 minutes, dry at room temperature and atmospheric environment for 20 to 28 hours at a relative humidity of 60 to 75%, and then the aluminum alloy superhydrophobic surface can be prepared . The invention has the advantages of simple operation process, good controllability, low cost, no complicated chemical treatment and expensive equipment, and easy industrialization.

Description

Preparation method for constructing superhydrophobic structure on aluminum alloy surface

technical field

The invention relates to a preparation method for constructing a superhydrophobic structure on the surface of an aluminum alloy in an atmospheric environment at room temperature.

Background technique

Metals are widely used in various departments of military industry, national defense, shipbuilding, construction and national production because of their excellent electrical and thermal conductivity, certain strength and good processability. However, ordinary metals are easily corroded in humid or corrosive environments, which affects the service life of the material, causes it to not function normally, and brings many unsafe factors to users. In recent years, superhydrophobic surfaces (material surfaces with water contact angles greater than 150° and water droplets have small rolling angles on surfaces) have attracted extensive research interest. Since the contact area of the liquid on the super-hydrophobic surface is very small, it can effectively inhibit surface oxidation, corrosion, frost, current conduction, etc. It falls without leaving any traces, which means that the super-hydrophobic surface can effectively reduce the chance of corrosive liquids in contact with metal materials, and help to improve the corrosion resistance of metal materials, which undoubtedly provides a basis for the research on the protection of metal materials. new direction of development. Therefore, superhydrophobic surfaces have broad application prospects in outdoor antennas, high-rise window frames, exterior wall coatings, ships, biomedical devices, microfluidics, and automotive windshields. For this reason, we choose the commonly used aluminum material as the research object.

The preparation of superhydrophobic surfaces is the key and the basis for the actual use of superhydrophobic surfaces in actual industrial and agricultural production and daily life. In recent years, a large number of techniques for preparing superhydrophobic surfaces have been developed, such as sol-gel method, fluorinated coating method, chemical vapor deposition method, electrochemical deposition method, polyelectrolyte alternate deposition method, anodic oxidation method, mechanical stretching method, etc. , plasma method, chemical etching method, electrospinning method, etc. However, these existing methods either use expensive materials such as fluorinated siloxane with extremely low surface energy, or require special processing equipment such as plasma processing equipment or complicated processes, so the cost is high and it is difficult to industrialize. Therefore, it is necessary to develop a simple and low-cost technique to prepare superhydrophobic aluminum alloy surfaces.

Invention content:

The technical problem to be solved by the present invention is to provide a simple and low-cost preparation method for constructing a superhydrophobic structure on the surface of an aluminum alloy.

In order to solve the above-mentioned technical problems, the preparation method for constructing a superhydrophobic structure on the surface of an aluminum alloy provided by the present invention comprises the following steps:

(1) Firstly, the aluminum alloy plate is mechanically polished and polished to remove surface defects and oxide films, and then cleaned with deionized water;

(2), 0.08mol/L oxalic acid solution and 1mol/L mass concentration are the hydrochloric acid solution of 3.7% by the volume ratio of 1: 1 and fully stir and make mixed acid solution;

(3) Immerse the aluminum alloy plate in the mixed acid solution for 12 to 18 hours, then take out the aluminum alloy plate and wash it thoroughly with deionized water, then immerse it in 0.5mol/L potassium permanganate solution for 1 to 2 hours, then use Wash with deionized water and dry in a furnace at 80-100°C for 0.5-1.5 hours;

(4) Soak in stearic acid ethanol solution with a mass fraction of 1% for 25 to 35 minutes, dry at room temperature and atmospheric environment for 20 to 28 hours at a relative humidity of 60 to 75%, and then the superhydrophobic aluminum alloy can be prepared surface.

In the above step (3), immerse the aluminum alloy sheet in the mixed acid solution for 15 hours, then take out the aluminum alloy sheet and wash it fully with deionized water, then immerse it in a 0.5mol/L potassium permanganate solution for 1 hour, and then wash it with deionized water Wash and dry in an oven at 80-100°C.

In the above-mentioned step (4), the stearic acid ethanol solution with a mass fraction of 1% was soaked for 30 minutes, and the relative humidity was 60 to 75%, and dried for 24 hours at room temperature and atmospheric environment.

In the preparation method for constructing a superhydrophobic structure on the surface of an aluminum alloy by adopting the above technical solution, the acid etchant used is: oxalic acid and hydrochloric acid. The surface coating materials used are: stearic acid, ethanol. The superhydrophobic base material can be pure aluminum or aluminum alloy. The contact angle between the superhydrophobic aluminum alloy surface and water is between 150° and 165°, and the rolling angle of water droplets on the surface of the material is less than 15°. The superhydrophobic property of the superhydrophobic aluminum alloy surface is stable, and the superhydrophobic property does not change after being placed in an environment with a temperature range of 0-40°C and a relative humidity of 30%-90% for one year.

In summary, the preparation method of the superhydrophobic aluminum alloy of the present invention has simple operation process, good controllability, good reproducibility, does not require any expensive equipment, and does not require complicated chemical treatment process, is easy to industrialize, and has great advantages. Good prospects for industrial application.

Description of drawings

Fig. 1 is the scanning electron micrograph of the superhydrophobic aluminum alloy surface that the embodiment of the present invention 1 obtains;

Fig. 2 is a test diagram of the contact angle between the superhydrophobic aluminum alloy surface and water obtained in Example 1 of the present invention.

Detailed ways

The present invention will be further described below in conjunction with drawings and embodiments.

Example 1:

First, the aluminum alloy plate is mechanically polished and polished to remove surface defects and oxide films, and then cleaned with deionized water. 0.08mol/L oxalic acid solution and 1mol/L hydrochloric acid solution with a mass concentration of 3.7% were mixed in a volume ratio of 1:1 and fully stirred to form a mixed acid solution; then the aluminum alloy plate was immersed in the mixed acid solution for 15 hours, and then Take out the aluminum alloy plate and wash it thoroughly with deionized water, then immerse it in 0.5mol/L potassium permanganate solution for 1 hour, then wash it with deionized water, and dry it in a furnace at 100°C for 1 hour. The aluminum alloy superhydrophobic surface can be prepared by immersing in stearic acid ethanol solution with a mass fraction of 1% for 30 minutes, drying at room temperature and air for 24 hours at a relative humidity of 75%. The wettability of the coating surface was tested with an OCA20 contact angle tester, see Figure 1 and Figure 2, the results showed that the contact angle of the surface with water was 154±2°.

Example 2:

First, the aluminum alloy plate is mechanically polished and polished to remove surface defects and oxide films, and then cleaned with deionized water. 0.08mol/L oxalic acid solution and 1mol/L hydrochloric acid solution with a mass concentration of 3.7% were mixed in a volume ratio of 1:1 and fully stirred to form a mixed acid solution; then the aluminum alloy plate was immersed in the mixed acid solution for 12 hours, and then Take out the aluminum alloy sheet and wash it thoroughly with deionized water, then immerse it in 0.5mol/L potassium permanganate solution for 2 hours, then wash it with deionized water, and dry it in a furnace at 80°C for 1.5 hours. The aluminum alloy superhydrophobic surface can be prepared by immersing in stearic acid ethanol solution with a mass fraction of 1% for 25 minutes, drying at room temperature and atmospheric environment at a relative humidity of 60% for 20 hours.

Example 3:

First, the aluminum alloy plate is mechanically polished and polished to remove surface defects and oxide films, and then cleaned with deionized water. 0.08mol/L oxalic acid solution and 1mol/L hydrochloric acid solution with a mass concentration of 3.7% were mixed in a volume ratio of 1:1 and fully stirred to form a mixed acid solution; then the aluminum alloy plate was immersed in the mixed acid solution for 14 hours, and then Take out the aluminum alloy sheet and wash it thoroughly with deionized water, then soak it in 0.5mol/L potassium permanganate solution for 1.5 hours, then wash it with deionized water, and dry it in a furnace at 100°C for 0.5 hours. The aluminum alloy superhydrophobic surface can be prepared by immersing in stearic acid ethanol solution with a mass fraction of 1% for 28 minutes, drying at room temperature and atmospheric environment at a relative humidity of 70% for 22 hours.

Example 4:

First, the aluminum alloy plate is mechanically polished and polished to remove surface defects and oxide films, and then cleaned with deionized water. 0.08mol/L oxalic acid solution and 1mol/L hydrochloric acid solution with a mass concentration of 3.7% were mixed in a volume ratio of 1:1 and fully stirred to form a mixed acid solution; then the aluminum alloy plate was immersed in the mixed acid solution for 18 hours, and then Take out the aluminum alloy sheet and wash it thoroughly with deionized water, then immerse it in 0.5mol/L potassium permanganate solution for 1 hour, then wash it with deionized water, and dry it in a furnace at 90°C for 1.2 hours. The superhydrophobic surface of the aluminum alloy can be prepared by immersing in stearic acid ethanol solution with a mass fraction of 1% for 35 minutes, drying at room temperature and air for 28 hours at a relative humidity of 75%.

Claims (3)

1. A preparation method for constructing a superhydrophobic structure on the surface of an aluminum alloy, characterized in that it may further comprise the steps: (1) Firstly, the aluminum alloy plate is mechanically polished and polished to remove surface defects and oxide films, and then cleaned with deionized water; (2), 0.08mol/L oxalic acid solution and 1mol/L mass concentration are the hydrochloric acid solution of 3.7% and mix and fully stir to make mixed acid solution by the volume ratio of 1:1; (3) Immerse the aluminum alloy plate in the mixed acid solution for 12 to 18 hours, then take out the aluminum alloy plate and wash it thoroughly with deionized water, then immerse it in 0.5mol/L potassium permanganate solution for 1 to 2 hours, then use Wash with deionized water and dry in a furnace at 80-100°C for 0.5-1.5 hours; (4) Soak in stearic acid ethanol solution with a mass fraction of 1% for 25 to 35 minutes, dry at room temperature and atmospheric environment for 20 to 28 hours at a relative humidity of 60 to 75%, and then the superhydrophobic aluminum alloy can be prepared surface. 2. the preparation method of constructing superhydrophobic structure on aluminum alloy surface according to claim 1, is characterized in that: in above-mentioned step (3), aluminum alloy plate is immersed in mixed acid solution for 15 hours, then takes out aluminum alloy plate and uses After fully washing with deionized water, immerse in 0.5mol/L potassium permanganate solution for 1 hour, then wash with deionized water, and dry in an oven at 80-100°C. 3. the preparation method of constructing superhydrophobic structure on the aluminum alloy surface according to claim 1 or 2, is characterized in that: in the above-mentioned step (4), in the stearic acid ethanol solution that massfraction is 1%, soak 30 minutes, The relative humidity is 60-75%, and it is dried for 24 hours under room temperature and atmospheric environment.

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