Temperature-stable Characteristics of Textured (Bi,Sm)ScO3-PbTiO3 Ceramics for High-temperature Piezoelectric Device Applications

Abstract

In this study, textured 0.38(Bi_0.97Sm_0.03)ScO₃-0.62PbTiO₃ (0.38BSS-0.62PT) ceramics with high Curie temperature were evaluated to assess temperature stable characteristics for high-temperature piezoelectric device applications. The 4 vol% BaTiO₃ incorporated 0.38BSS-0.62PT ceramic was fabricated by conventional tape casting. Textured 0.38BSS-0.62PT ceramic was successfully produced at sintering temperature of 1150°C by textured grain growth (TGG). Textured 0.38BSS-0.62PT ceramic exhibited a high degree of crystal orientation of 94% in the [001]-direction. It also showed excellent dielectric and piezoelectric properties, (ε^T₃₃/ε₀ of 1746, d₃₃ of 719 pC/N, k_p of 61.8% and g₃₃ of 45×10^-3Vm/N, respectively). In addition, it also exhibited relaxor-like ferroelectric characteristics with a large relaxation coefficient (γ) of 1.77 along with high Curie temperature of approximately 373℃. Its temperature stability was satisfactory, resulting from in-situ d₃₃ and k_p, which were lower than 10% below Curie temperature. The electro-strain also showed thermally stable characteristics. Therefore, it is considered that the textured 0.38BSS-0.62PT ceramic has potential for high-temperature piezoelectric device applications.