Effect of SrO on piezoelectric, dielectric and ferroelectric properties of (Ba_(1-x) Sr_x) (Ti_(0.98) Zr_(0.02))O_3 lead free piezoceramics

摘要

Effect of SrO on piezoelectric, dielectric and ferroelectric properties of (Ba_(1-x) Sr_x) (Ti_(0.98) Zr_(0.02))O_3, (x = 0.00, 0.01, 0.015, 0.02 and 0.03 mol) lead free piezoceramics was studied. The powders were prepared by "mixed oxide" route, calcined at 1,000 ℃ for 4 h. XRD patterns of the calcined powders confirm the orthorhombic phase. The calcined powders were de-agglomerated, pressed into pellets and sintered at 1,150 ℃ for 3 h. Scanning electron microscopy studies of thermally etched sintered pellets show increase in the grain size with the increase in SrO concentration. The piezoelectric charge constant (d_(33) = 330 pC/N), dielectric constant (K = 2,337) and remnant polarization (P_r = 4.69 (μC/cm~2) were maximum for 0.015 mol of SrO. The temperature versus dielectric constant graph was plotted for 0.015 mol SrO doped BZT and the Curie temperature was found to be 116 ℃.