Structure-property relationships in strontium barium niobate II. Quenching and annealing effects

Abstract

The effects of quenching and annealing have been studied in Sr_xBa_1-xNb₂O₆ (SBN x/(1 - x)) by dielectric spectroscopy and transmission electron microscopy. The relaxor characteristics of the dielectric response were found to be suppressed after quenching from 800°C. Subsequent dielectric investigations during thermal cycling below 400°C revealed thermal hysteresis effects between consecutive heat and cooling measurements. The original relaxor characteristics of the as-grown state were completely recovered by thermal treatment near 400°C. Similar changes in the relaxor characteristics were observed after quenching from 1000°C. However, complete recovery was not obtained on subsequent thermal treatment until above 800°C. Dark-field imaging using 1/x[110] incommensurate reflections revealed a decrease in the size of nanoelastic domains on quenching, and an increase in the size of needle-like nanopolar domains.