Bio-Inspired Porous Anodic Alumina/Aluminum Flake Powder for Multi-Band Compatible Low Detectability

Continuous development and advancement in modern detection technologies have increased demand for multi-band (e.g. visual, infrared) compatible camouflage. However, challenges exist in the requirements of incompatible structure resulting from the adaptation to different camouflage effects. This study is inspired by the light absorption structure of butterfly wing scales and demonstrates porous anodic alumina/ aluminum flake powder material, prepared by microscopic powder anodic oxidation technique for visual and infrared camouflage. The fabricated structures manipulate compromise condition for visual camouflage by low reflectance (R(400~800 nm)=0.32) and dual-band infrared camouflage by low emission (ε(3~5 μm)=0.081 and ε(8~14 μm)=0.085). Further, the characteristic of short-range disorder in these bio-inspired structure allows maintenance of the camouflage performance under omni-directional detection (0~60°). This study provides new insight and feasible method for coordinated manipulation of electromagnetic waves via bio-inspired structural design and improved fabrication.