2017 年 54 巻 1 号 p. 41-45
Tailoring the crystallographic orientation in ceramics is very useful for improving their properties. A magnetic field is shown to be very effective in controlling the crystallographic orientation in bulk ceramics. The particles were rotated to an angle minimizing the system energy by a magnetic torque generated from the interaction between the magnetic anisotropy and the applied magnetic field. This processing was applied to control the microstructure in lanthanum silicate oxyapatite (LSO) for SOFC and LiCoO2 for Li ion secondary battery. Electric conductivity parallel to the c-axis in the c-axis oriented LSO was higher than that perpendicular to the c-axis. The battery performance of the ideal textured cell fabricated using a rotating magnetic field has a significantly higher performance than a oriented cell prepared by a static magnetic field.