Effects of Nb 2 O 5 additive on the piezoelectric and dielectric properties of PHT‐PMN ternary ceramics near the morphotropic phase boundary

Recently, a new family of piezoelectric perovskite materials, PbHfO 3 ‐PbTiO 3 ‐Pb(Mg 1/3 Nb 2/3 )O 3 (PHT‐PMN) ternary system was developed, possessing good piezoelectric properties and high Curie temperature near the morphotropic phase boundary (MPB). Nb 2 O 5 , as a donor dopant in the perovskite piezoelectric systems has been used to improve the dielectric and piezoelectric properties. In this work, the effect of Nb 2 O 5 addition in the PHT‐PMN ternary system was reported. It was found that Nb doping led to the change of phase structure for the PHT‐PMN system. With the addition of Nb 2 O 5 content, the ferroelectric polarization was reduced, while the electric‐field‐induced strain and hysteresis were enhanced significantly. In particular, the 0.2 wt% Nb 2 O 5 ‐doped PHT‐PMN exhibited the optimum piezoelectric and electromechanical properties, with d 33 and k p being on the order of 670 pC N −1 and of 71%, respectively.