In order to study the influences of interfaces on magnetoelectric (ME) coupling, a finite element model for multiferroics composites was suggested by employing cohesive zone elements for the interfaces. Piezoelectric elements were utilized for both piezoelectric and piezomagnetic phases based on the analogy between piezoelectric and piezomagnetic constitutive relations. And cohesive zone models (CZM) were employed to represent the relation between tractions and displacement discontinuities on imperfect interfaces, which characterized the stiffness and toughness of interfaces and were implemented by cohesive zone elements. Imperfect interfaces can be modeled by adopting CZM parameters, and perfect interfaces are also possible to be approximately modeled by CZM with enhanced interfacial stiffness. Example results of laminated multiferroics composites with ideal interfaces show good agreement with those in literature. The influences of imperfect interfaces on ME coupling were analyzed by the present finite element model, the corresponding ME coefficients were calculated. The simulation results indicate that the interface stiffness plays a significant role on ME coefficient of the composites. When the interfaces are stiff enough, they tend to be perfect and the ME coefficient tends to a constant. The present method and results are of reference significance to process of interfacial bonding and prediction of ME properties.
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