We study the spatial distribution of reoriented domains in ferroelectric ce
ramics of calcium modified lead titanate (Pb1-xCaxTiO3) with different Ca c
ontents and their behaviour with temperature. These results are related to
the electric relaxation process of the studied ceramics and the electric be
haviour of these materials. To make this study, a method based on low frequ
ency sinusoidal thermal waves was used.