Remarkably high-temperature stable piezoelectric properties of Bi(Mg0.5Ti0.5)O3 modified BiFeO3–BaTiO3 ceramics

Dense (1-x)BiFe1-x(Mg0.5Ti0.5)xO3–yBaTiO3 (BFMT-BT, y=0.29, x=0-0.12) ceramics with a pseudocubic perovskite crystal structure exhibit remarkably high-temperature stable piezoelectric properties. In particular, x=0.03 BFMT-BT ceramics, with a Curie temperature, Tc, of ~425C, show a stable piezoelectric coefficient, d33, of ~155 pC/N up to a depolarization temperature, Td, of ~400C. This Td is higher than Tc for Pb(Zr,Ti)O3, therefore suggesting BFMT-BT ceramics to be promising high-temperature Pb-free piezoelectric materials.