Ultrahigh electrostrictive strain and its response to mechanical loading in Nd-doped PMN-PT ceramics

Electrostrictive materials play an important role in the development of high precision actuators, due to the advantages of high resolution, low power dissipation and fast response time. However, the practical application of electrostrictive materials has been hindered by their limited displacement output. To address this, we conducted a study where we doped Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) ceramics with Nd2O3, aiming to significantly improve the electrostrictive effect by enhancing local structural heterogeneities that disrupt the formation of long-range ordered ferroelectric domains. We obtained an optimized electrostrictive strain of 0.231% with negligible hysteresis at an electric field of 50 kV/cm in 4%Nd-doped PMN-PT ceramic, surpassing the performance of state-of-the-art lead-based electrostrictive ceramics. Of particular significance is that a high electrostrictive coefficients M33 = 12.2×10−16 m2/V2, together with a high mechanical work density of 0.035 J/cm3 and a low power dissipation of 14%, was achieved under a mechanical prestress of 50 MPa and an electric field of 10 kV/cm. Additionally, this material exhibits excellent fatigue resistance, with less than 3% variation over 106 operation cycles. All these findings position 4%Nd-doped PMN-PT ceramics as a promising candidate for high-performance electromechanical actuator applications.