Effect of Annealing Process on Porous Aluminium Filled with Graphite

Thermal properties of porous thin films formed by anodization of thin aluminum films in sulfuric acid. The obtained pores at the surface are filled by sprayed graphite which the role is to improving its optical and thermal absorption giving a structure of an assembly of three different media such as graphite/(Porous aluminium layer filled with graphite)/(Al sample). The realized structure is annealed in temperature range varying from the room temperature to 650ºC for various durations. Thermal properties of the realized structure was studied by Photothermal Deflection (PTD) Technique and correlated to the microstructure evolution. It was found that this structure is characterised by thermal conductivity which, conversely to thermal diffusivity, increases with the heating duration and temperature in the furnace and can be used in solar energy field.