Fine Grain BaTiO3-Co0.5Ni0.5Fe2O4 Ceramics Prepared by the Two-Stage Sintering Technique

Abstract

This work investigated the improvement of density and controllable grain size of multiferroic ceramics by using the system of (0.8)BaTiO3-(0.2)Co0.5Ni0.5Fe2O4 nanocomposites via the two-stage sintering technique. The sintering process was divided into two steps. Firstly, samples were fired at the optimized temperature of T1 to activate grain boundary migration in order to obtain an initial high density. Secondly, the samples were cooled immediately to the temperature of T2 and soaked at various times to enable dense ceramics without grain growth. All of the samples were characterized by an X-ray diffractometer, and the results confirmed that all samples were composite ceramics. Scanning electron microscopy showed the grain size of all the samples and proved that the two-stage sintering technique achieved fine grain ceramics when compared with traditional sintering. Electrical properties of all the samples were investigated using an LCR meter at room temperature to 200°C with various frequencies, and magnetic properties were characterized by a vibrating sample magnetometer.