Aluminium alloy processed by square‐column composite structure and its anti‐icing characteristics

To prepare surfaces with stable anti‐icing properties, square‐column micro/nanocomposite structures were fabricated using wire‐cut electrical discharge machining. Smooth and hydrophobic/superhydrophobic surfaces were tested for wettability and were subjected to mechanistic analysis. Droplets were found to produce an ‘air cushion effect’ upon contact with the microstructure, which reduced the contact area between the droplets and the aluminium substrate and increased the contact angle of the droplets on the surface. The icing experiment quantitatively evaluated the anti‐icing performance of the surfaces by observing the cooling time and out‐of‐phase icing time of water droplets. It was found that the anti‐icing effect is influenced by the wettability of the material and that the superhydrophobic surface has excellent anti‐icing properties. Combined with the one‐dimensional heat transfer theory for analysing the mechanism of icing, the results show that the ‘air cushion’ reduces the heat transfer between the solid and liquid and increases the thermodynamic barrier to ice core formation. The stability of the sample surface was tested by icing‐melting experiments and friction experiments, and the test piece exhibited stable wettability and anti‐icing performance.