Papers by Keyword: Ferroelasticity

Abstract: Ionic devices consisted of ion-conductive ceramics such as solid oxide fuel cells (SOFC) and oxygen separation membranes have been developed in the last decades. La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF), which is a mixed ionic-electronic conductive ceramics, is especially expected to play an important role in those ionic devices and so its electrochemical properties have been intensively studied.

Abstract: In order to incorporate the mechanical behavior of ferroelastic phase into the stress analysis of solid oxide fuel cell in consideration of elastic, creep, thermal and reduction strains, we propose a mathematical model to predict the formation of ferroelastic phases in crystal grains of La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ. The phase field model equipped with the elastic energy is introduced to realize the morphology formation of ferroelastic phases in a crystal grain. By the use of the developed mathematical model, some numerical examples are performed to reproduce the deformation-induced nucleation and growth of ferroelastic phases of La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ.

Abstract: La_1-xBa_xCoO₃ single crystals were grown from KOH melt at 873 K under H₂O/O₂ mixed gas flow. The grown crystals had a parallelepiped form with the edges of about 60 μm. Streaks indicating twin boundaries were observed on the surface planes of the crystals. The crystals showed magnetic anisotropy and anomalous MH hysteresis loops. The magnetocrystalline anisotropy and coupling of ferroelasticity and ferromagnetism were discussed based on the magnetic properties.