IMF2017

The Lead has recently been expelled from many commercial applications and owing to concerns regarding its toxicity. Currently, piezoelectric ceramic materials in commercial use are based on lead titanate zirconate (PZT), which are widely used in sensors, actuators and other electronic devices. The basic approach to achieving high piezoelectricity is to place the composition of the material to the proximity of a composition-induced phase transition between two ferroelectric phases. Such a transition has been known as the morphotropic phase boundary (MPB) in the phase diagram. Therefore, in the present work, the compounds (1-x)(Ba_0.77Ca_0.23)TiO₃-xBa(Ti_0.85Zr_0.15)O₃ (1-xBCT-xBZT x = 0.25, 0.50 and 0.75) have been prepared through solid state reaction of BCT and BZT compounds. The compositions were sintered at 1320 ^oC for 2 h in a furnace. The final density of each sintered specimen was determined by the Archimedes method and the grain sizes were investigated using a scanning electron microscopy (FEI). The phase transitions studies were performed in several temperatures using a Rigaku Ultima IV diffractometer (HT 1500 high temperature attachment). Electrical measurements were carried out with a Solartron SI 1260 impedance/gain-phase analyzer over a wide temperature range from 25 to 200 ^oC. The phase transitions were also studied using the dilatometry technique (Netzsch-DIL 420C) and the differential scanning calorimetry (DSC) techniques (Netzsch-STA 409C). The combination of all these techniques allows us to have an overall view of the BCT-BZT phase transitions behavior.