Dielectric Properties of Unsintered Barium Titanate

Abstract

Dielectric properties of pure, unsintered and pressed barium titanate were investigated. The initial nonlinear variation of dielectric constant and dissipation factor with temperature observed is attributed to the water vapor adsorbed on the surface exposed to the pores. The absence of ferroelectric properties and the linearity in dielectric constant and dissipation factor with temperature found in a heat-treated sample are explained on the basis of a nonferroelectric surface layer. This was supported by the experiment showing the decrease in dielectric constant with decreasing particle size.