Characterization of modified lead titanate piezoceramics. Application to the design of array transducers

Due to their high electromechanical anisotropy, lead titanate piezoelectric ceramics of modified composition are very interesting for designing either linear or annular ultrasonic transducer arrays used in medical diagnosis and in non-destructive testing. In this paper results of the characterization of three varieties of this type of material are presented. The characterization includes the measurement of the resonance frequency dispersion diagram of thin parallelepipedic elements and the measurement of the characteristics in the longitudinal thickness mode and the planar mode. In view of the application to the design of transducers, several types of structures are presented.