In situ XRD analyses for asymmetric responses of poled PLZT ceramics during electric fatigue

Abstract

Electric fatigue behaviors of the poled lanthanum-doped lead zirconate titanate (PLZT) ceramics were investigated using a home-made electric loading apparatus in conjunction with a conventional X-ray diffractometer. The XRD data were measured under actions of the applied direct current electric fields on the as-received poled PLZT specimens being experienced various cycles (10N) of alternating current (AC) electric fields. Experimental data showed that in addition to apparent degradation in remnant polarization, asymmetries in hysteresis loops and fraction of 90° domain switching curves were observed. It was found that an offset electrical field (\(\Delta {{\text{E}}_N}\)) was induced in the poled specimen by polarization with its direction against the direction of the polarization. Furthermore, the magnitude of \(\Delta {{\text{E}}_N}\) and the degree of asymmetry (δN) decreased as the number of AC electric fatigue cycles (10N) varied from 100 to 106. In situ XRD data suggested that the poled specimen exhibited different abilities to reorient a-domains into c-domains when the applied electric fields were opposite. The δN not only depended linearly on \(\Delta {{\text{E}}_N}\), but also on abilities of the poled specimen to reorient a-domains into c-domains.