LAUSR

Abstract The mechanism by which Bi 0.5 Na 0.5 TiO 3 and Bi 4.5 Na 0.5 Ti 4 O 15 templates are synthesized via a topochemical microcrystal conversion method using Bi 4 Ti 3 O 12 precursor and TiO 2 particles was investigated based on their crystal structures. The Bi 0.5 Na 0.5 TiO 3 template consisted of a mixture of plate-like and equiaxed particles, whereas the Bi 4.5 Na 0.5 Ti 4 O 15 template consisted only of plate-like particles. The size of the plate-like and equiaxed particles was dependent on the size of the Bi 4 Ti 3 O 12 precursor and TiO 2 particles, respectively. The Lotgering factor and piezoelectric constant of textured Bi 0.5 (Na 0.8 K 0.2 ) 0.5 TiO 3 ceramics prepared using the Bi 0.5 Na 0.5 TiO 3 template were lower than those of the textured Bi 0.5 (Na 0.8 K 0.2 ) 0.5 TiO 3 ceramics prepared from the Bi 4.5 Na 0.5 Ti 4 O 15 template. This can be attributed to the small amount of plate-like particles in the Bi 0.5 Na 0.5 TiO 3 template caused by the inevitable co-existence of equiaxed particles.