THERMAL DEPOLING EFFECTS ON ANISOTROPY OF LEAD-ZIRCONATE-TITANATE MATERIALS

Changes in elastic anisotropy and fracture toughness anisotropy of a l ead zirconate titanate (PZT) piezoelectric material as a function of d epoling temperature were investigated using ultrasound and Vickers ind entation. A gradual transition from anisotropic to isotropic propertie s occurs with increased depoling temperatures at and above the Curie t emperature. Depoling is also evident through changes in domain charact er revealed by X-ray diffraction, The relationship between the mechani cal properties and domain structure variation with respect to differen t depoling conditions is discussed.