Two bonded multiferroic ceramics half-planes with coupled interfacial imperfections: In-plane fracture and its dislocation-based physical mechanisms

• In-plane fracture analysis is performed on two bonded multiferroic half-planes.
• The multiferroic composite contains coupled interfacial imperfections.
• Effects of shielding, anti-shielding, interference and anti-interference are revealed.
• Two dislocation models are proposed to explain the fracture mechanisms.

Essentially speaking, both crack and interfacial imperfection can be regarded as continuously distributed dislocations. Therefore, the fracture behavior of composites containing imperfect interfaces may be explained by the interactions of different distributed dislocations. The purpose of this paper is to make a try on such explanation. For this purpose, in-plane fracture analysis is performed on two bonded multiferroic half-planes with coupled interfacial imperfections by the methods of Fourier integral transform and Green's functions. Numerical results of the mechanical strain energy release rate are obtained by numerically solving the Cauchy singular integral equations of the crack problem. The effects of the three kinds of interfacial imperfections and their inter-couplings on the fracture behavior are discussed based on the variations of mechanical strain energy release rate versus the interface parameters, and the fracture behavior including shielding, anti-shielding, interference and anti-interference are revealed, respectively. Finally, the cracks and the imperfect interface are simulated as continuously distributed dislocations to construct two types of dislocation distribution models, which are then, for the first time, employed to explain the mechanisms of the fracture behavior.