Ferroelasticity in mixed conducting LaCoO3 based perovskites: a ferroelastic phase transition

The defect structure of LaCoO3 based ferroic perovskites has been studied by TEM. The dynamics of the temperature-induced ferroelastic to paraelastic phase transition was directly monitored by in-situ TEM during thermal cycles from room temperature to 700DGC. Different types of structural features of LaCoO3 based perovskites have been observed, such as twins, antiphase domains, stacking faults, and dislocations. Domain motion and de-twinning during heating, and the reappearance of twins during cooling have been demonstrated. This is important for the understanding of ferroelastic hysteretic behavior of LaCoO3 based perovskite ceramics.