Measurement of all the elastic, piezoelectric, and dielectric properties of PMN-PT single crystals

PMN-PT single crystals have rhombohedral 3m symmetry. In this paper, all the elastic, piezoelectric, and dielectric constants of the PMN-PT single crystals were measured by the resonance method. For the rhombohedral symmetry, a total of twelve independent material constants were measured such as six elastic compliance constants at constant electric field, two dielectric constants at constant stress, and four piezoelectric constants d. Seven sets of the crystal samples of each different geometry were prepared for the measurement of length-thickness extensional, thickness extensional, radial, length extensional and thickness shear modes of vibration, respectively. In order to check the validity of the measurement method, the same technique was applied to the characterization of common PZT ceramics. Experimental impedance spectrum of the PZT ceramics was compared with numerical impedance spectrum calculated with measured material constants. The good agreement between the two spectra confirmed validity of the characterization method in this paper.