Moisture detection in composite materials using infrared thermography

This paper presents the results obtained by a non-destructive evaluation method, developed in our laboratory, to detect absorbed moisture in composite materials. We use the particular dielectric properties of water molecules under microwave excitation, to create local heating in the material and detect it by an infrared thermography camera. With appropriate numerical processing, thermograms are analysed and used to locate moisture containing zones. We have applied it to damaged glass-fibre composite plates exposed to humid environments.