Development of glass-ceramic seali̇ng materials from natural rock basalt and waste glasses for solid oxide fuel cell

Solid oxide fuel cells (SOFC) are environmentally electrochemical devices that directly convert chemical energy to electricity and heat energy. Glass-ceramic material group has the best properties in providing sealing in KOYP. In this study, three different the mixtures including natural volcanic rock basalt, waste window glass and Na2CO3 were development for using as sealants. The prepared mixtures were melted at 1500° C and cast into the water and graphite mold. Glass cast into graphite mold were used in dilatometer analysis to determine the coefficient of thermal expansion. Glass cast into water were milled and sized -53 µm and after certain pretreatments, coated on Crofer, AISI 430, 409, 439 and 441 stainless steel by dip coating method. After the coating, heat treatment was performed at 850, 900 and 950 °C in order to ensure permanent bonding and sealing between glass-ceramic sealing and steel substrate. As a result of the heat treatment, transformation from glassy structure to glass-ceramic structure occurred. The interface between glass-ceramic sealing and steel substrate, bonding and sealing properties were examined by scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) to determine its suitability for SOFC.