Dielectric and electromechanical properties of barium titanate single crystals grown by templated grain growth

Single crystals of BaTiO3 were grown by templated grain growth (TGG). TGG i nvolves contacting a single crystal "template" to a sintered polycrystallin e matrix, then heating the assemblage to a temperature that promotes the mi gration of the single crystal boundary through the matrix. In this investig ation the properties of millimeter-sized, plate-shaped and bar-shaped, sing le crystals of BaTiO3 grown by TGG were examined in order to compare the re sults to single crystals grown by conventional methods. A dielectric consta nt, epsilon(33)(T)/epsilon(0), of 260, polarizations of P-R similar to 16 m u C/Cm-2 and P-sat similar to 21.5 mu C/cm(2), electromechanical coupling c oefficients of k(33) similar to 0.51 and k(31) similar to 0.18, and a piezo electric coefficient of d(33) similar to 140 pC/N were achieved. Entrapped porosity in the crystals made fully poling the crystals difficult.