Temperature-insensitive PMN-PZ-PT ferroelectric ceramics for actuator applications

Piezoelectric actuators are essential for numerous electromechanical applications, because of their advantages of high resolution, large generated forces, no friction, low heat dissipation and fast response. The design of the next-generation piezoelectric actuators is desired to meet the complex needs of advanced machines and instruments, where the high-performance and stable output under the combined thermal and mechanical loads are expected. However, simultaneously achieving high-performance and good temperature stability of piezoelectric actuators is a challenge, which hinders the use temperature range in practical applications. Here, in the studied Sm-doped Pb(Mg_1/3Nb_2/3)O₃-PbZrO₃-PbTiO₃ system, the high piezoelectric strain coefficient d₃₃* = 870 pm/V with superior temperature stability (below 7% variation over the temperature of 20°C to 280°C), together with negligible property degradation up to 10⁶ cycles was successfully achieved. The outstanding blocking stress of 37.2 MPa and mechanical work of 6.4 kJ/m³ were obtained under the driving electric field of 15 kV/cm. This work provides a paradigm to achieve high piezoelectric strain properties with good temperature stability, where the studied materials are expected to greatly benefit the development of high temperature piezoelectric actuator applications.