The effect of Cr2O3 addition on crystallization and properties of La2O3-containing diopside glass-ceramics

We report on the effect of La2O3 and Cr2O3 on the structural, thermal and crystallization behavior of diopside-based glasses and on the processing, microstructure and properties of the sintered glass-ceramics (GCs). The structural features and thermal behavior of the glasses were investigated by Fourier transform infrared spectroscopy, density measurements, dilatometry and differential thermal analysis. The sintering, crystallization, microstructure and properties of the GCs were investigated under different heat treatment conditions (800-1000 degrees C; 1-300 h). The good matching of thermal expansion coefficients and the strong, but not reactive, adhesion to yttria-stabilized zirconia and Crofer 22 APU alloy, in conjunction with a low level of electrical conductivity, indicates that the investigated GCs are suitable candidates for further experimentation as solid oxide fuel cell sealants. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.