ELECTROSTRICTIVE PROPERTIES AND POLARIZATION MECHANISMS OF Pb(Zn_1 /_3Nb_2/_3)O_3 BASED CERAMICS
铌锌酸铅基陶瓷的电致伸缩特性与极化机制

The.electrostrictive properties. hysteresis loops and dielectric properties of Pb(Zn1 /3Nb2/3)O3-BaTiO3-PbTiO3(85-10-5, 80-10- 10, 75- 10-15) have been carefully measured as a function of field strength, measurement frequency and temperature. Comparing with the dielectric response,the microscopic nature of polarization mechanisms and the variation of the strain vs polarization squaredwith the compositions are discussed. The different contribution to field-induced strain ofmicordomains and macrodomains are stressed. These two kinds of domain have different character in small signal measurement and large field measurement.