Electrostrictive effect and dielectric properties of lead-free 0·5Ba(Zr_xTi_1–x)O₃–0·5(Ba_0·75Ca_0·25)TiO₃ ceramics near morphotropic phase boundary (MPB) compositions

Abstract

The ceramics of 0·5Ba(ZrxTi1–x)O3–0·5(Ba0·75Ca0·25)TiO3(x = 0·15, 0·20, 0·25 and 0·30) (BZT–BCT) were synthesized by the conventional solid-state reaction method. And then, the dielectric, ferroelectric and electrostrictive properties of the ceramics were investigated near morphotropic phase boundary (MPB). Meanwhile, its crystallographic structure had been found to change from tetragonal phase to pseudocubic phase by the raising Zr⁴⁺ content from 0·15 to 0·30. And the grains morphology was observed from SEM. Finally, when the ceramics sintered at 1400°C for 2h with x = 0·15, The excellent properties were obtained: The electrostrictive strain reaches 0·16% under 40 kV cm^− 1, and T _m=102°C, which demonstrated that the BZT-BCT has superior strain capacity as a lead-free system.

Keywords:

• BZT–BCT
• Dielectric
• Ferroelectrics
• Electrostriction