Surface processing method of super-hydrophobic ice-covering-proof aluminum and steel with rough surface

Abstract

The invention relates to a surface processing method of super-hydrophobic ice-covering-proof aluminum and steel with rough surfaces. The method comprises the following steps: performing ultrasonic cleaning to aluminum and steel plates with acetone and deionized water, drying, suspending the aluminum and steel plates in a sealed container with 20vol.%-80vol.% of hydrochloric acid solution, then etching aluminum and steel plates with volatile hydrochloric acid for 15min-1h in a water bath under the temperature of boiling water, namely 100 DEG C; after the etching, placing the aluminum and steel plates in the normal hexane solution of fluorosilane to performing evaporation and modification of fluorosilane at 200-300 DEG C for 1-2h, and finally taking out the samples to keep temperature in the air at 180-300 DEG C for 1-2h; and in the fluorosilane solution, the weight ratio of fluorosilane to normal hexane is 1-5%, and the pH value of the added acetic acid aqueous solution is 3 and the content is 2-4% of the normal hexane solution of fluorosilane.

Description

technical field [0001] The invention relates to a surface treatment method for super-hydrophobic ice-coated aluminum and steel with rough surfaces. Background technique [0002] Frosting phenomenon widely exists in metal parts of refrigeration and low-temperature operating equipment, such as air coils of heat pump units, wings and surfaces of aerospace vehicles, air conditioners, inner surfaces of refrigerators, etc., which brings differences to the stable operation of equipment degree of harm. [0003] The traditional anti-icing technology on the surface of engineering materials mostly uses mechanical or heating technology to de-ice and melt ice, such as thermal ice melting, over-current ice melting, short-circuit ice melting, and load-bearing ice melting. Some existing inventions and technologies are also based on the idea of ​​"melting ice", such as: using high-frequency pulse current heating and oscillation method to prevent and de-ice the transmission and distribution ...

AI Technical Summary

Problems solved by technology

For example, after stirring organosilane and / or fluorosilicone resin, quick-drying solvent, and main solvent at room temperature, successively add polyethylene oxide, silane coupling agent accelerator, silicon oxide and / or aluminum oxide particles and stir, and finally coat on the test surface. The anti-icing coating can be obtained by solidifying the surface of the sample, which can reduce the amount of frosting by 40%. However, this technology is not easy to coat some parts of equipment and parts with complex shapes, which makes the protection uneven, and the organic solvent in the coating is volatile. , the service life is low, and the frost layer also needs to be removed under mechanical vibration, which has certain limitations for some precision instruments, equipment and parts that need anti-icing but cannot be vibrated; through vacuum evaporation, on the surface of power transmission cables Coating n-hexacane hydrophobic layer can also delay the formation of initial frost crystals, and the formed frost crystals have a loose structure and are easier to remove. However, it should be pointed out that this coating method requires a vacuum degree of -5 It is obviously not easy to carry out large-scale production under vacuum conditions

[0005] Studies have shown [Byeongchul N, Ralph LW, Int.J Heat & Mass Transfer, 2003, 46, 3797-3808], the roughness of the solid surface will reduce the supersaturation of water vapor, thereby reducing the nucleation rate and nucleation speed of water droplets , to delay the formation of initial frost crystals and play the role of frost suppression. At the same time, the barrier of water droplets forming on the hydrophobic surface is larger than that on the hydrophilic surface, so the number of liquid nuclei condensed on the hydrophobic surface is smaller than that on the hydrophilic surface .Therefore, constructing roughness and hydrophobicity simultaneously on solid surfaces, especially aluminum and steel surfaces that are widely used, will more effectively delay the appearance of initial frost crystals and significantly improve the anti-icing performance of aluminum and steel surfaces. But Based on this idea, there have been no reports on the hydrophobic anti-icing technology for aluminum and steel surfaces.

Images