Caracterización de materiales piezocerámicos de potencia

A comparative study of the methods to measure the nonlinearities that appear in the piezoceramic materials, when they are used in power devices, is developed. A phenomenological model, allowing the measure and characterization of these nonlinearities, is proposed. It explains the effects produced: increase of losses, shift of resonant frequency and hysteresis. A discussion about which is the variable which governs these nonlinearities, what are the magnitudes that we must measure, and what measurement system permits to carry out these measurements, is made.