화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.99, No.3, 922-929, 2016
Highly Textured BaTiO3 via Templated Grain Growth and Resulting Polarization Reversal Dynamics
Samples of bulk textured polycrystalline BaTiO3 ceramics were fabricated using a templated grain growth (TGG) approach in order to investigate effects of polycrystallinity and texture related to ferroelectric domain reversal under high-power drive conditions. Barium titanate platelets were formed via two-step topochemical conversion of bismuth titanate platelets grown via molten salt synthesis, then aligned via tape casting within a matrix of fine BaTiO3 powder. The coarse-grained parts showed a high degree of crystallographic texture after sintering. Combined with ceramics of similar density and polycrystallinity, but random orientation and commercial single-crystal specimens, this sample set enabled direct isolation of crystallographic texture and polycrystallinity as the primary variables for high-power polarization reversal studies. These studies have also demonstrated a link between grain size and polarization reversal time that strongly suggests that grain boundaries serve effectively as nucleation sites during the ferroelectric switching process.