Remarkable piezoelectricity and stable high-temperature dielectric properties of quenched BiFeO3-BaTiO3 ceramics

Effects of quenching process on dielectric, ferroelectric, and piezoelectric properties of 0.71BiFeO(3)-0.29BaTiO(3) ceramics with Mn modification (BF-BT-xmol%Mn) were investigated. The dielectric, ferroelectric, and piezoelectric properties of BF-BT-xmol%Mn were improved by quenching, especially to the BF-BT-0.3 mol%Mn ceramics. The dielectric loss tan delta of quenched BF-BT-0.3 mol%Mn ceramics was only 0.28 at 500 degrees C, which was half of the slow cooling one. Meanwhile, the remnant polarization P-r of quenched BF-BT-0.3 mol%Mn ceramics increased to 21 mu C/cm(2). It was notable that the piezoelectric constant d(33) of quenched BF-BT-0.3 mol%Mn ceramics reached up to 191 pC/N, while the T-C was 530 degrees C, showing excellent compatible properties. The BF-BT-xmol%Mn system ceramics showed to obey the Rayleigh law within suitable field regions. The Rayleigh law results indicated that the extrinsic contributions to the dielectric and piezoelectric responses of quenched BF-BT-xmol%Mn ceramics were larger than the unquenched ceramics. These results presented that the quenched BF-BT-xmol%Mn ceramics were promising candidates for high-temperature piezoelectric devices.