Influences of magneto-electro-elastic layer properties of piezoelectric/piezomagnetic composites on dynamic intensity factors

Abstract

Magneto-electro-elastic (MEE) materials are composed of piezoelectric (PE) and piezomagnetic (PM) phases, leading to the existence of a large number of interfaces between phases. Complex interface distributions bring a challenge for the dynamic fracture analysis of MEE composites, as the available fracture mechanics approaches usually need to avoid material interfaces. This work establishes a dynamic domain-independent interaction integral (DII-integral) to extract the dynamic intensity factors (IFs) for MEE materials. The DII-integral exhibits apparent superiority over available I-integral methods in the dynamic fracture studies of MEE composites with complicated interfaces due to its domain-independence for interfaces and avoidance of material property derivatives. After verifying the accuracy, the DII-integral method is applied to investigate the dynamic fracture of PE-MEE-PM layered composites. It is found that as the crack tip approaches the MEE middle layer, the dynamic IFs decrease for a crack in PE phase (BaTiO3) but increase for a crack in PM phase (CoFe2O4). The elastic stiffness, PE coefficient, PM coefficient and dielectric permittivity of MEE middle layer have a significant effect on the dynamic IFs, and the other material parameters have slightly effect.