Molecular dynamics study on wetting behavior of aluminum plates with different surface energies by microstructure difference

Abstract

Wettability is the main factor that affects the self-cleaning and corrosion resistance of metal surfaces. The main factor that affects wettability is the change of surface microstructure and surface energy of metal material. When modifying metals, it is necessary to master their wetting behavior to obtain the required performance surface. In this paper, the wetting behavior of liquid droplets on smooth, square, papillary and nail-shaped surfaces with different surface energies was studied systematically by molecular dynamics simulation. The results show that the solid–liquid interaction factor is negatively correlated with the surface contact angle of aluminum plate. When the solid–liquid interaction factor is greater than the droplet potential energy parameter, the nail-shaped surface has the largest solid–liquid contact area and droplet centroid displacement rate due to its large roughness, and the surface hydrophilicity is the best; When the solid–liquid interaction factor is close to the droplet potential energy parameter, the nail-shaped surface has the smallest solid–liquid contact area and droplet centroid displacement rate due to its large roughness, and realizes the transition from neutral to hydrophobic; When the solid–liquid interaction factor is less than the droplet potential energy parameter, the papillary surface has the smallest solid–liquid contact area and droplet centroid displacement rate due to its small solid–liquid area fraction, thus realizing the transition from hydrophobicity to superhydrophobicity. The simulation results of this study are consistent with the classical theoretical calculation and experimental results, which reveals the interaction between metal surface wettability and surface energy and surface morphology.