Devitrified Barium Titanate Dielectrics

Abstract

The findings allow the prediction of densities achievable in an aggregate of angular particles by purely mathematical methods. The predicted densities show agreement within *0.015 with densities achieved in practice. Prediction of achievable densities of aggregates of angular particles by this method reduces the time and inaccuracies involved in graphical solutions or extrapolations from similar systems. Pure barium titanate was made into a glass by flamespraying and after sufficient comminutionwas processed into specimens and fired. During this firing the glass devitrified to tetragonal barium titanate and contained crystals of sizes from 0.5 to below 0 . 2~. The small crystals exhibit Curie temperatures from 120° to above 185OC. The dielectric Curie temperature of the devitrified ceramic is 150° to 155OC.

The role of ceramic and glass science research in meeting societal challenges: Report from an NSF‐sponsored workshop

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