Study On The Icing Characteristics Of Superhydrophobic Silicone Rubber Surfaces By Nanosecond Laser Texturing

In low-temperature climate environments,the problem of ice coating on its surface is an important factor affecting the reliability and stability of electric transportation.At present,the methods of mechanical deicing,heating deicing and salt water spray not only consume a lot of manpower and material resources,but also it is difficult to obtain a satisfactory deicing effect.Since increasing the hydrophobicity of the silicone rubber surface can improve its anti-icing performance to a certain extent,but its icing characteristics are more closely and directly related to the surface microstructure morphology and particle size.Therefore,how to effectively control the surface morphology and particle size of superhydrophobic silicone rubber to achieve good anti-icing performance needs further in-depth research.In response to this problem,this thesis uses laser texturing to adjust the wettability and structure morphology of the silicone rubber surface,and specifically analyzes the mechanism of the influence of its surface structure morphology and particle size on its icing characteristics.The morphological characteristics and ice particle state of the droplets on the ordinary silicone rubber and superhydrophobic silicone rubber surface during the cooling process were compared and analyzed.The results show that at room temperature,the contact between the untreated silicone rubber surface and the droplets is in the Wenzel state.During the icing process,the ice core will be formed in the center of the bottom of the water droplet at the earliest,and gradually extend to the surface as the temperature decreases,finally form a conical ice particle.In the icing process of droplets on the superhydrophobic sample surface,the outer surface will first form an extremely thin ice layer,which gradually solidifies and extends upward from the bottom of the water droplet,and finally wraps the water droplet.During the cooling process,the contact state of water droplets with the sample surface is characterized by"Wenzel state around the bottom and Casie state in the center".Superhydrophobic silicone rubber surfaces with different microstructures were prepared by changing the parameters of laser texturing,and the effect of different surface microstructures on the icing characteristics and ice coating was further investigated.The results show that when the laser fluence density reaches 10 J/cm~2,the prepared superhydrophobic surface has larger particle size and richer distribution levels,and the actual contact area of the surface with water droplets is smaller.During the cooling process,the air in the tiny gap on the surface will seal the solidified droplets in the gap,so the surface can show the longest droplet solidification time,especially when the sample surface temperature drops to-18℃,the contact angle of the surface can still be maintained at～140°.Further investigate the anti-icing effect of superhydrophobic surfaces in practical applications,the state of the ice coating on each surface was tested.The results showed that the silicone rubber prepared with the laser fluence of 10 J/cm~2 has the smallestadhesion strength to the ice coating,and after 30 cycles of icing and deicing,its surface still maintains excellent hydrophobic properties.During the accelerated aging process,the superhydrophobic surface also showed good stability.The analysis results prove that the specific microstructure state of the superhydrophobic surface has a significant effect on its anti-icing performance.In this thesis,it is feasible and reliable to change the laser texturing parameters and adjust the microstructure state of the superhydrophobic silicone rubber surface to obtain good ice resistance.