Crack propagation induced by incompatible domain switching in BaTiO3 crystal under electric field loading. (15th October 2021) - Li, Yingwei
Highlights: Crack propagation behavior in BaTiO3 (BTO) crystal under electric field was in situ investigated. Three modes of crack propagation induced by incompatible domain switching were proposed. The practical electrical boundary condition of fresh natural crack was proven to be permeable. Abstract: Using a system composed of a polarized light microscopy and a charge coupled device (CCD), the crack propagation behavior in BaTiO3 (BTO) crystal under electric field was in situ investigated with the field direction parallel or perpendicular to the crack surface. In addition, the growth behavior of Vickers indentation surface cracks under alternating electric field was also in situ investigated. Three crack propagation modes induced by incompatible domain switching were proposed based on our observation. The electrical boundary condition of the crack surface was also characterized by measuring and comparing the hysteresis loop of a perfect BTO crystal without crack and a BTO crystal completely fractured in half. Results demonstrate that the electrical boundary condition of a fresh natural crack is permeable, and evolves from permeable to partial permeable during cyclic electric field loading.