Fabrication and electrical properties of textured Sr_0.53Ba_0.47Nb₂O₆ ceramics by templated grain growth

Textured Sr_0.53Ba_0.47Nb₂O₆ ceramics with a relative density of >95% were fabricated using templated grain growth (TGG). Acicular KSr₂Nb₅O₁₅ template particles synthesized via a molten salt process were aligned by tape casting in a mixture of solid-state-synthesized SrNb₂O₆ and BaNb₂O₆ powders. The resulting ceramics possessed strong fiber texture along the polar axis ([001]) of the strontium barium niobate. Samples with 15.4 wt% templates attained a textured fraction of 0.82 after sintering at a temperature of 1450 °C for 4 h. These materials showed peak dielectric constants of 7550 at 1 kHz, remanent polarizations of 13.2 μC/cm², saturation polarizations of 21 μC/cm² (60%-85% of the single-crystal value), piezoelectric strain coefficients of 78 pC/N (70%-85% of the single-crystal value), and room-temperature pyroelectric coefficients of 2.9×10^-2 μC·(cm²·°C)^-1 (52% of the single-crystal value). These results show that TGG is a viable option for accessing single-crystal properties in polycrystalline ceramics.