Dielectric and piezoelectric properties of textured Sr0.53Ba0.47Nb2O6 ceramics prepared by templated grain growth

Abstract

Fiber textured Sr0.53Ba0.47Nb2O6 ceramics were reactively sintered to greater than or equal to95% of the theoretical density from a mixture of SrNb2O6 and BaNb2O6 powders. Texture in 001) was obtained by templated grain growth on [001]-oriented acicular KSr2Nb5O15 template particles. The most highly textured ceramics had a peak dielectric constant of 23,600 (at T-c = 128 degreesC), a remanent polarization (P-r) of 20.3 muC/cm(2), a saturation polarization (P-sat) of 24 muC/cm(2) (69-96% of single crystal), and a piezoelectric charge coefficient (d(33)) of 84 pC/N (76-93% of single crystal). A model, correlating polarization with grain orientation, predicts that P, increases sharply when a percolating grain network forms to transfer charge between elongated grains.