Fracture Behavior and Degradation of Piezoelectric Properties in PZT

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J. Korean Ceram. Soc. > Volume 29(10); 1992 > Article

Journal of the Korean Ceramic Society 1992;29(10): 806.

PZT의 파괴거동 및 압전 열화특성

태원필, 김송희, 조상희¹

강원대학교 재료공학과
¹경북대학교 무기재료공학과

Fracture Behavior and Degradation of Piezoelectric Properties in PZT

ABSTRACT

The aim of this study was to investigate the change in compressive strength, freacture behavior and degradation of piezoelectric properties with compressive cyclic loading in Pb(Zr, Ti)O3 of tetragonal, morphotropic phase boundary and rhombohedral composition. The highest compressive strength was found in rhombohedral composition. After poling treatment the strength increased by 8.4% and 6.5% in tetragonal and morphotropic phase boundary compositions respectively while changed little in rhombohedral. The increase of compressive strength after poling treatment is believed to be due to the internal stress around grain boundary by domain alginment toward electric field direction in the microstructures having tetragonality and the occurrence of domain switching to the direction perpendicular to electrical field during fracture. Fracture mode relatively change from transgranular to intergranular was observed in the large grain sized tetragonal and morphotropic phase boundary compositions before and after poling but the transgranular fracture mode always remained in the rhombohedral composition. From the X-ray diffractometer analysis the domains parallel to the electric field direction is known to undergo rearrangement during the cyclic loading into random direction that is responsible for the degradation of piezoelectric property.