Temperature dependence of the electrical, mechanical and electromechanical properties of high sensitivity novel piezoceramics

The temperature dependence of the S,3 T dielectric permittivity and losses of piezoelectric Mn doped 0.65Pb(Mg1/3Nb2/3)O-3-0.35PbTiO(3) ceramics has been measured up to 350degreesC at frequencies between 1 and 100 kHz by impedance spectroscopy The temperature dependence of the low frequency Young's modulus and mechanical losses of the ceramics has been measured in the same temperature range by dynamic mechanical analysis in three points bending configuration. Complex epsilon(33)(T), s(II)(E) compliance and d(31) piezoelectric coefficients have been obtained from radial piezoelectric resonances at temperatures tip to 90degreesC (before depolarisation) by an automatic iterative method. All the measurements reflect the occurrence of the ferroelectric rhombohedral to ferroelectric tetragonal phase transition, which is thougth to be responsible of the high electromechanical response of the PMN-PT system, and allow describing some of its characteristics for the investigated ceramics.