Field induced domain switching as the origin of anomalous lattice strain along non-polar direction in rhombohedral BiScO₃-PbTiO₃ close to the morphotropic phase boundary

The lattice strain and domain switching behavior of xBiScO₃-(1-x)PbTiO₃ (x=0.40) was investigated as a function of cyclic field and grain orientation by in situ X-ray diffraction during application of electric fields. The electric field induced 200 lattice strain was measured to be five times larger than the 111 lattice strain in pseudorhombohedral xBiScO₃-(1-x)PbTiO₃ (x=0.40). It is shown that the anomalous 200 lattice strain is not an intrinsic phenomenon, but arises primarily due to stress associated with the reorientation of the 111 domains in dense polycrystalline ceramic.