Effect of uniaxial stress on the dielectric properties of BaTiO 3 +0.1wt.%Eu 2 O 3 ceramics.

BaTiO3+0.1wt.%Eu2O3ceramics were prepared by a solid-state reaction method. The dielectric behavior of these ceramics as a function of uniaxial pressure has been systematically studied. The external stress showed obvious effects on these properties. An increase of the Curie point (Tc) and decrease of the Curie–Weiss temperature (T0) was observed with increasing pressure, resulting in an increase in the first-order nature of the phase transformation (Tc–T0increases). Broadening and flattening of the permittivity versus temperature curves near their maximum was found. The pressure behavior of thermal hysteresis and the ∂ϵ/∂Tvs.Tplot suggests that the phase transition changes to second-order type with increasing pressure. Furthermore, the Curie–Weiss constant obtained from a modified Curie–Weiss law strongly decreases with increasing pressure, suggesting that the mechanism of phase transition is going to order–disorder type. [ABSTRACT FROM AUTHOR]