Nanomechanical characterization of BiFeO3 ferroelectric ceramics.

Ferroelectric perovskites are pivotal in diverse technological applications; however, a gap persists in our comprehension of their mechanical properties, emphasizing the need for additional exploration. In the present study, we report on the nanomechanical behavior of BiFeO 3 ceramics in the force range between 200 μN and 2 mN, including the evolution of the hardness and the reduced Young's modulus from (9.9 ± 0.4) GPa and (113.7 ± 6.9) GPa, respectively, with increasing force. A sequence of plastic-deformation mechanisms under the cube-corner probe was revealed through a first pop-in analysis in combination with a variety of electron microscopy techniques, starting with a homogeneous dislocation nucleation, multiplication and rearrangement leading to sub-grain formation, a phenomenon observed in metals but not in ceramics. [ABSTRACT FROM AUTHOR]