Effects of BaO–SiO2 glass particle size on the microstructures and dielectric properties of Mn-doped Ba(Ti, Zr)O3 ceramics

The sintering behavior, microstructures and dielectric properties of Mn-doped Ba(Ti, Zr)O3 (BTZ) ceramics with different particle sizes of BaO–SiO2 glass (D50 ranging between 185 and 1200 nm) were investigated. From the metallographic observation, adding finer glass frit revealed more homogeneous compositional distribution. It was found that better spreading of the glass phase could be achieved by adding finer glass particles that could penetrate the BTZ ceramic interface more easily, thus enhancing the grain growth. The extent of the incorporation between glass and ceramic increased with smaller glass particles, and the Curie temperature was altered accordingly. Microstructural evaluation conducted by using X-ray diffraction (XRD) and transmission electron microscopy (TEM) with an energy-dispersive X-ray spectrometer (EDS) indicated the glass particle size has a dramatic influence on the sintering behavior and microstructure of Mn-doped BTZ ceramics. The relationship between microstructures and dielectric properties was also discussed in this study.