Thermodynamic Stability of Yttrium Alkaline Earth Borosilicate Glasses and Their Compatibility with Crofer for SOFC

Abstract

Crystallization kinetics and stability are very important and essential parameters for glasses and glass ceramics. These parameters are highly dependent on initial composition as well as processing conditions. Thus, the role of modifier cation on thermal parameters have been studied for AO-SiO 2 -B 2 O 3 -Y 2 O 3 (A Ca, Sr, Ba) glasses. Various kinetic parameters such as fluctuation free volume (f g ), change in bulk thermal expansion coefficient ( f ) and frequency factors (k y (T p ), k b (T p ), k f (T p )) have been calculated for better understanding of crystallization mechanics of present glasses. According to these parameters, CaO- SiO 2 -B 2 O 3 -Y 2 O 3 glass shows good thermodynamic and kinetic stability than other two glasses. The morphology of Crofer22APUglass-ceramics diffusion couples (heat-treated at 850°C for 50 h) were analyzed by SEM and EPMA. The kinetic parameters and microstructural studies of glasses showed an excellent correlation with each other. CaYCrofer22APU couple showed good interfacial adhesion along with minimum diffusion of ions on either side of the interface. © 2012 The Electrochemical Society.