Influence of Hydrothermal Conditions on Size of Template Particles for Textured Ceramics

We report the influences of the sodium dodecyl-benzenesulfonate (SDBS), hydrothermal reaction temperature and time on the size of potassium sodium niobate (K,Na)NbO3 (KNN) template particles to determine the regularities of these changes. In the reaction with a small autoclave, when the quantity of SDBS reached 1.5wt%, the width of the obtained platelike KNN-hydrate particles reached a maximum of 1.5 mu m and the thickness was 0.15 mu m, meaning that the aspect ratio was 10/1. To accommodate practical applications, a large autoclave was used in the following hydrothermal reaction. We found that the size of the platelike particles increased with improved reaction temperature and time. Particles 1.5 to 5 mu m wide and 0.15 to 0.4 mu m thick were prepared. After calcining these particles at 450 degrees C, platelike KNN template particles were obtained. Finally, tape-casting results showed that the platelike KNN templates have the (100) orientation. (C) 2011 The Japan Society of Applied Physics