Construction And Anti-icing Performance Of The Hydrophobic Aircraft Aluminum Alloy Surface

During the flight of the aircraft,the phenomenon of icing on the surface of the fuselage due to passing through the cold clouds will have a huge impact on flight safety.At present,the common anti-icing methods will complicate the design of the aircraft,which is not consistent with the lightweight of modern aircraft.The paper studies an anti-icing technology based on the surface modification of materials and explores its potential in aviation applications.A 2524 aluminum alloy for aviation is used as a research material to study the preparation method and low-temperature hydrophobic properties of micro-structured hydrophobic surfaces.Based on this,the micro-nano composite surfaces with induced direction that can transport droplets quickly is proposed.And then different micro-structured surfaces anti-icing performance was tested and comprehensively evaluated.The main contents are as follows:(1)Using 2524 aluminum alloy as the material,the effects of laser process parameters such as scanning number of laser beam,average power and scanning speed on the surface micron-level morphology and hydrophobicity at low temperature,and the effects of wet etching process parameters such as hydrochloric acid etching concentration,etching time and reaction temperature on surface nanometer morphology and hydrophobicity at low temperature were studied.Based on this,two process were combined to obtain a micro-nano composite structure.(2)Anti-icing performance tests were performed on the temperature-controlled platform on the prepared surfaces with different microstructures based on static droplet freezing delay,ice layer adhesion strength,and condensation characteristics.Treated samples can be extended by nearly 10 times at-10℃ in terms of icing delay,the ice layer adhesion is reduced by 75%,and the droplet coverage during condensation is much smaller than that of the untreated smooth surface.(3)The prepared samples were subjected to dynamic single-droplet impingement surface experiments and directional droplet continuous ejection experiments at low temperature.The dynamic water repellent experiments show that the impact time of the droplets on the surface mainly depends on the contact angle lag.The smaller the contact angle lag,the shorter the contact time.The continuous droplet ejection experiment found that micro-grooves with a certain size can guide the transport of droplets.In view of the directivity of the aircraft a micro-nano surface with direction induction was designed.By adjusting the surface structure,the transport efficiency of droplets on the grooved surface with a hundred-micron level was as high as 97%.Finally,the static droplet anti-icing experiment and the dynamic droplet continuous impact experiment were compared to evaluate the icing quality at low temperature to comprehensively evaluate the specific anti-icing capabilities of the two in use.It was found that the micro-nano composite surfaces with induced direction in which droplets can be transported quickly makes a better anti-icing ability in the actual anti-icing of the micro-nano composite surface,which proves that the surface can improve the anti-icing performance.