PIEZOELECTRIC AND RELAXOR MATERIALS SYNTHESIZED BY HYDROTHERMAL PROCESSING

The hydrothermal process was employed to produce lead- and barium-base d perovskites at different conditions of temperature and time. The pow ders were characterized by atomic absorption spectroscopy, X-ray fluor escence spectrometry and X-ray diffraction in order to estimate the im purity levels and the presence of the perovskite phase. Density, surfa ce area and porosity of the powders were determined by helium pycnomet ry, nitrogen adsorption technique and Sedigraph. These parameters were correlated to the processing conditions. The pressed powders were sub mitted to complex impedance spectroscopy measurements in the frequency range 5 Hz-13 MHz. The results showed crystalline powders with differ ent morphologies and adequate dielectric properties for the applicatio ns as piezoelectric and relaxer ferroelectrics.