Study of ferroelastic behavior and microstructure in polycrystalline LaCoO3 using Transmission Electron Microscopy

Abstract

LaCoO 3  is a ferroelastic perovskite-type oxide. It has been shown to undergo creep at room temperature. LaCoO 3  responds to stress by changing its domain structure, resulting in formation of spontaneous strain. The microstructure of a sample of polycrystalline LaCoO 3  with history of stress was investigated using Transmission Electron Microscopy (TEM). It was compared to an unstrained sample to determine what changes are produced. TEM analysis has shown an increase in defect density as well as the appearance of atomic scale ordering. The causes of the observed ordering and their relation to ferroelastic behavior are explored.