MnO2-Modified Ba(Ti,Zr)O3 Ceramics with High Qm and Good Thermal Stability

MnO2-modified Ba(Ti0.9625Zr0.0375)O3 ceramics have been prepared by the conventional solid-state reaction technique at different sintering temperatures. Room-temperature piezoelectric properties, thermal stability, and crystalline structures were investigated. It was found that both the MnO2 additive and sintering temperature significantly influence the piezoelectric properties of the MnO2-modified Ba(Ti0.9625Zr0.0375)O3 ceramics. The sample sintered at 1400°C exhibited the best room-temperature piezoelectric properties of Qm = 1907, d33 = 205 pC/N, and kp = 40.5% with tan δ = 0.46%, and its kp remains larger than 35% in the broad temperature range from −38°C to 65°C. The results indicate that MnO2-modified Ba(Ti0.9625Zr0.0375)O3 ceramics are promising lead-free materials for frequency device and power device applications.