Dielectric and electromechanical behaviors of PMN-PT ceramic samples

The results of the investigations on (1 - x)PMN-xPT ceramic samples obtained by sol-gel (SG) technology are presented in this study. In the (I - x)PMN-xPT samples, the temperature T-m (at which real part of dielectric permittivity reaches its maximum) increases from approximate to 270 K for x = 0 to approximate to 500 K for x = 0.5. At room temperature, the samples with low values of x exhibit relaxor properties, while with increasing x the transition to normal ferroelectric properties takes place. Usually 0.9PMN-0.1PT or 0.925PMN-0.075PT solid solutions are considered as boundary compositions between relaxor and ferroclectric properties at room temperature. This study presents the analysis of X-ray diffraction patterns, fracture microphotographs, electromechanical parameters, and hysteresis loops for ceramics obtained from SG PMN-PT powders densified by the hot pressing method with a composition range, x=0-0.37.