Prof. Nina Orlovskaya, University of Central Florida
March 14, 2011
11:00 AM - 12:00 PM
Ferroelasticity and Hysteresis in LaCoO3 based Perovskites
Abstract:
Perovskite-type ABO3 (where A=La, Ca; B=Co) ceramics are very promising materials for oxygen separation membranes, solid oxide fuel cells, oxygen sensors, and catalysts. Recently we reported that LaCoO3 based perovskites exhibit ferroelastic to paraelastic phase transition during heating cycles. In this research we demonstrated ferroelastic to paraelastic phase transition in La0.6Ca0.4CoO3, characterized the microstructural and pase stability of LaCoO3 at high temperatures, investigated microstructural changes during heating, dwelling at high temperature, and cooling cycles by in-situ high temperature TEM. As a result of ferroelastic transition, lanthanum cobaltites exhibit ferroelasticity and hystersis upon loading. We studied the mechanical performance of perovskites using microindentation, compresion and bending. Ferroelastic hystertic behavior of LaCO3 based perovskirtes has been demonstrated. Domain switching under compression has been confirmed by XRD. Room temperature time dependent creep deformation has been studied. An unusual “anti-creep” behavior has been discovered in pure LaCoO3. The research is important for the development of reliable devices which mechanical integrity of the materials employed
Additionally a short review of other research topics will be briefly outlined: “Manufacturing of lower temperature SOFCs”, “Stability and mechanical performance of Sc2O3-CeO2 doped zirconia”, “Design of touch ceramic laminates by residual stresses” and “Thin film coating on the interconnect materials for SOFCs.
Date posted
Jun 17, 2019
Date updated
Jun 17, 2019