A highly controlled fabrication of porous anodic aluminium oxide surface with versatile features by spatial thermo-anodization

Thermo-anodization technology has been considered as an effective means to improve the thermal, physical and chemical properties for metal alloy. In this work, we achieve a porous black layer on the surface of aluminium alloy through an environmentally friendly anodic oxidation process, with a high thermal emittance (0.96) and a high solar absorptivity (0.921). In addition, the black thermo-anodized coating layer shows a unique anti-corrosion property under UV irradiation. A hybrid hydrophobic surface has been facilitated through treating the thermo-anodized porous layer with silane. Moreover, an anti-icing feature can be realised that can effectively delay the freezing of water droplet on the surface of AA2024 aluminium alloy. As such, the specific anodic process of coating provides a simple method for improving the solar absorptivity and infrared emittance of aluminium alloys, enabling broad applications in aerospace engineering.

Automated summary

Research focuses on achieving a porous black layer on the surface of aluminium alloy through an environmentally friendly anodic oxidation process, with high thermal emittance and solar absorptivity; the black thermo-anodized coating layer shows unique anti-corrosion property under UV irradiation; a hybrid hydrophobic surface and anti-icing feature can be realized through post-treatment with silane.