Chemical interaction and thermal studies of calcium borosilicate glass sealants

Abstract

Crystallization kinetic studies of glasses are very important to understand the effect of the formation of various crystalline phases on sealing properties. These crystalline phases may degrade the performance of solid oxide fuel cells. The formation of these phases mainly depends on the raw materials used in making the glasses and processing conditions. Thus, the role of intermediate cations on the crystallization kinetics of CaO–B2 O3–SiO2–A2 O3 (A=Y, La, Cr, Al) glasses was studied using various techniques. Isothermal heat treatment at 800°C of the synthesized glasses resulted in surface crystallization of different crystalline phases. Based on the results of the crystallization kinetics studies, the La2 O3 containing glass was selected for an interaction study with the interconnect material Crofer22APU. The interface and diffusion couples were investigated using scanning electron microscopy and energy dispersive spectroscopy