Revealing the origin of thermal depolarization in piezoceramics by combined multiple in-situ techniques

Abstract Thermal depolarization is an insurmountable obstacle to the application of piezoceramics and there is still controversy about its physical origin. In this work, taking four representative piezoceramics (0.94(Na 0.5 Bi 0.5 )TiO 3 -0.06BaTiO 3 , 0.2Pb(Zn 1/3 Nb 2/3 )O 3 -0.8Pb(Zr 0.5 Ti 0.5 )O 3 , 0.36BiScO 3 -0.64PbTiO 3 and Ba 0.85 Ca 0.15 Ti 0.9 Zr 0.1 O 3 ) as an example, by using a designed in-situ Berlincourt-type high-temperature d 33 meter, combined with variable temperature X-ray diffraction and dielectric temperature spectrum test, it was confirmed the depolarization behavior is directly related to the structural phase transition, meanwhile it is reasonable to apply the peak value of piezoelectric coefficient with temperature, T dp , as the depolarization characteristic temperature. More importantly, the original in-situ varied temperature d 33 meter design helps to investigate the temperature dependent piezoelectric mechanism of various piezoceramics.