Direct observation of the stress-induced domain structure in lead-free (Na1/2Bi1/2)TiO3-based ceramics

Abstract

In this work, the creep behavior of (Na1/2Bi1/2)TiO3-0.07BaTiO3 was characterized as a function of bias stress up to −500 MPa, revealing the time-dependence of the stress-induced relaxor-to-ferroelectric long-range order transformation. Creep strain was observed across a range of applied compressive stress levels, in particular at stresses approximately 50% above the critical coercive stress, indicating the significant time-dependence of the transformation on the long-range ferroelectric order. The macroscopic behavior is discussed in conjunction with ex situ piezoresponse force microscopy measurements that directly show the formation of ferroelectric domains in mechanically loaded relaxor ferroelectrics.