Influence of burnout process on pore structure and burnout microstructure in BaTiO3-based Y5V materials

BaTiO3-based multilayer ceramic capacitors (MLCCs) prepared by tape casting, showing Y5V characteristic, were fired with different burnout conditions. MLCCs show the delamination from the heating rate of 7 °C/min to 200 °C, and 6 °C/min to 250 and 300 °C in the ambient atmosphere, without the delamination in the reducing atmosphere. The pore size distribution of MLCCs becomes narrower with increases in the temperature and heating rate, showing larger pore size and mono-modal pore size distribution. The cumulative pore surface area shows minimum values at a higher temperature and faster heating rate in both atmospheres. However, MLCCs of the reducing atmosphere display a smaller cumulative pore surface area than that of the ambient atmosphere. The microstructure related to the burnout process is more dependent on atmosphere and temperature than heating rate. The possible causes for the burnout behavior and microstructure are also discussed.