Abstract:
This paper aims to investigate the effects of temperature and pressure on the stability of superhydrophobic surface performance. Through detailed experiments and analyses of the surface properties and contact angles of superhydrophobic materials, the influence of temperature and pressure variations on superhydrophobic performance is explored. Superhydrophobic surfaces were prepared by laser processing aluminum plates followed by surface fluorination treatment. The contact angle variation with experimental temperature and pressure were investigated.After laser processing and fluorination, the water droplet contact angle on the surface exhibited minimal dependence on processing parameters. When groove spacing and depth remained constant, the contact angle gradually decreased with increasing temperature. Notably, on surfaces with cross-groove nominal widths of 50 μm, droplets underwent a transition from the Cassie to Wenzel wetting state. Under compressive pressure, the contact angle displayed fluctuations as pressure increased, accompanied by an overall reduction in contact angle and eventual Cassie-Wenzel state transition. The multi-scale structural characteristics of laser-processed surfaces contribute to the insensitivity of contact angle to structural parameter variations; Heating-induced reduction in liquid surface tension and increased actual liquid-solid contact area lead to decreased contact angles and potential Cassie-Wenzel transitions; Microstructural discontinuities on the surface lead to contact angle fluctuations when a droplet on a superhydrophobic surface is pressed.