Effect of high energy mechanical milling on hysteresis and dielectric properties of Ca_xBa_1−xZrxTi_1−xO₃ (x = 0 and 0.1) ferroelectric materials

Powders of ferroelectric materials with general formula Ca_xBa_1−xZr_xTi_1−xO₃ (x = 0 and 0.1) synthesized by solid state reaction were milled in a planetary ball mill in air, with tungsten carbide vial and 150 tungsten carbide balls of diameter 10 mm for 12 h, 18 h and 30 h. The powder x-ray diffractometry was employed to confirm the single phase tetragonal (P4 mm) perovskite structure for all the specimens. From PE hysteresis studies, polarization decreased, while coercivity and remanence increased with ball milling time up to 18 h and decreased for 30 h milled specimens. The dielectric constants of both the ferroelectric specimens showed universal dielectric response with frequency variation in the range of 100 Hz –1 MHz as well as with milling duration. (paper)