Characterization of Pb-free BZT-BCT ceramics synthesized by solid state reaction process

The following samples of lead free samples (1-x)[Ba_0.92Zr_0.08TiO₃]-(x)[Ba_0.92Ca_0.08TiO₃]. (x=0,0.25,0.5,0.75,1) abbreviated as BZT-BCT were prepared in laboratory by solid state reaction process. The samples were prepared keeping in mind their applications in actuators, sensors. The samples were then tested for their dielectric, piezoelectric, pyroelectric properties and dc resistivity. Each sample showed a maximum dielectric constant in the adjoining regions of the Curie temperature (T_c). Moreover, strain measurement, density measurement and P-E loop were also done to examine the prepared pellets. The microstructure of BZT-BCT pellets was investigated using Scanning Electron Microscope. The microstructure of the sintered samples depends on the method of preparation as well as Ca and Zr content. Larger contents of Ca yield smaller grain size. The average size of the ceramics were determined using X-ray Diffraction. The XRD patterns show shifting of the position of diffraction peaks at higher angles with increase in calcium content and decrease in zirconium content. After a series of experiments conducted on the sample, the results were worth noting. It can be observed that a piezoelectric charge constant greater than 400 is suitable for actuator applications.