IMPEDANCE ANALYSIS OF LAYER STRUCTURED NBT-CBT MIXED CERAMICS

Complex impedance spectra of ferroelectric mixed ceramic system (Na0.5 Bi0.5)(1-x)Ca-x Bi4Ti4O15 With x = 0, 0.1, 0.3, 0.6, 0 7 and 1 was stu died as a function of frequency and temperature in the range 1 KHz to 10 MHz and 30 degrees C to 620 degrees C respectively. Equivalent circ uits involving resistive and capacitive elements at different temperat ures, activation energies of relaxations and conduction were evaluated using impedance plots. A comparative study of impedance and conductiv ity facilities an insight in understanding the electrical nature of th ese electroceramics.