Abstract
Nonlinear character of the dielectric response and the behavior of longitudinal ultrasonic waves velocity in a piezoceramic material 0.36PbTiO3–0.33PbZrO3–0.17Pb(MgZn)1/3Nb2/3O3–BaTiO3–SrZrO3 based on PZT are studied. It is established that anomalies in the temperature-field dependences of the effective permittivity ε´eff(E,T) and the velocity of the longitudinal ultrasonic wave v(T) arise in the temperature region, substantially below the temperature of the permittivity maximum Tm = 160 °C. The nature of these anomalies indicates the relaxor-like properties of this type of ferroelectric ceramics, where the coexistence of different phase states of the material is possible in a wide temperature range.