Abstract:

The adhesion enhancing effect induced by electro-magnetic loading and the adhesion weakening effect resulting from interfacial shear stress have been observed and widely reported in open literature. However, the adhesion behavior of multiferroic composites in the simultaneous presence of these two effects and the competitive mechanism between them are still unclear. In this paper, the non-slipping adhesive contact problem between a multiferroic half-space and a perfectly conducting rigid cylinder subject to multi-field loading is studied. The stated problem is reduced to a system of coupled singular integral equations, which are analytically solved with the analytical function theory. The closed-form solutions of the generalized stress fields including the contact stress, normal electric displacement, and magnetic induction are obtained. The stable equilibrium state of the adhesion system is determined with the Griffith energy balance criterion. The adhesion behavior subject to mechanical-electro-magnetic loading and a mismatch strain is discussed in detail. Numerical results indicate that exerting electro-magnetic loading can enhance the adhesion effect for both two types of multiferroic composites, namely, \kappa-class (non-oscillatory singularity) and \epsilon-class, which is different from the case of piezoelectric materials. It is found that the contact size finally decreases in the simultaneous presence of the electro-magnetic enhancing and shear-stress weakening effects. The results derived from this work not only are helpful to understand the contact behavior of multiferroic composites at micro/nano scale, but also have potential application value in achieving switchable adhesion.

Key words: adhesive contact, multiferroic composite, analytical solution, non-slipping, Johnson-Kendall-Roberts (JKR) model