Colour simulation and prediction of complex nano-structured metal oxide films: Test case: Analysis and modeling of electro-coloured anodized aluminium

An optical modeling procedure is developed to predict and model the colour of electro-coloured anodized aluminium that has been modified in pore structure for the generation of interference colours. The relation between the multi-layered, nano-sized oxide microstructure and the colour is experimentally determined and translated into an optical model that is able to predict the colour as a function of microstructural variations. The optical modeling procedure is highly sensitive to changes on the nano-scale (porosity, percentage of metal deposition, presence of barrier regrowth…), and has high potential as a predictive tool to relate the microstructure of a surface to the final colour characteristics of the metal, and as such to the used electrolytic processing conditions.