Composition dependent ferro-piezo hysteresis loops and energy density properties of mechanically activated (Pb1-xLax)(Zr0.60Ti0.40)O3 ceramics

In the present study, ferroelectric and piezoelectric nature of La substituted lead zirconate titanate was investigated to decide the optimum La content. (Pb1-xLax)(Zr0.60Ti0.40)O-3 (hereinafter PLZT x/60/40) ceramics were synthesized using novel processing approach of high energy ball milling and cold isostatic pressing (CIP). This study deals with two types of hysteresis loops, polarization (P-E) and strain vs. electric field (S-E) loops. Energy density properties, remanent polarization (P-r), coercive field (E-c), piezoelectric charge coefficient (d(33)), internal macroscopic electric field (E-in), domain switching current (I-max) and strain hysteresis, normalized strain coefficient (S-max/E-max) were also calculated to study the behaviour of PLZT x/60/40 ferroelectrics. In addition, current vs. electric field (I-E) curves were traced not only to support P-E studies and determination of the E-c but also to confirm the ferroelectricity and domain switching characteristics studies. The PLZT 8/60/40 electro-ceramics not only show the highest P-r similar to 29.1 mu C/cm(2), I-max similar to 2 mA, unipolar strain similar to 0.25% and average d(33) similar to 632 pm/V but also the lowest E-c similar to 9.4 kV/cm and strain hysteresis loss similar to 4%.