Modelling ferroelastic domain switching at a stationary crack tip in a single crystal with account of transformation stresses due to domain reorientation

The present paper deals with ferroelastic domain switching around a stationary crack tip in a single crystal for potential applications in the context of crack toughening. The main focus is directed towards the effect of transformation stresses on the domain. The transformation stresses themselves are coupled to the extent and the shape of the domain. Therefore, they and the domain are unknown a-priori and have to be determined simultaneously. The model is applied to a crack in barium titanate and indicates a major effect of the transformation stresses on the observed needle-like domain shapes. Comparison with experimental observations shows a reasonable agreement although essential properties of barium titanate as ferroelectricity and piezoelectricity are neglected yet.