Fabrication of BaTiO3 single crystals using secondary abnormal grain growth

During secondary abnormal grain growth (SAGG) of BaTiO3, some grains were observed to grow extensively. This phenomenon has been implemented for the fabrication of BaTiO3 single crystals. When a BaTiO3 powder compact was sintered at 1365°C, a small number of secondary abnormal grains appeared. The sintered specimen was then further heat-treated at 1355°C. At this temperature, the preexisting secondary abnormal grains continued to grow without forming the new ones. BaTiO3 single crystals larger than 1 × 1 cm could thus be obtained by such a two-step heat-treatment.