The Effect of Surface Tension in Modeling Interfacial Fracture

In this article the problem of an interface fracture between two isotropic linear elastic materials is studied within a continuum modeling framework, which incorporates important nanoscale effects. The proposed model of bi-material crack ascribes curvature-dependent surface tension to both the fracture surfaces and the solid-solid interface. Further, it uses as boundary conditions the jump momentum balance equations, which take into account the excess properties ascribed to the material interfaces. Ultimately, the model leads to a 4×4 system of Cauchy-singular integro-differential equations which is equivalent to a system of Fredholm integral equations. It is demonstrated herein, using the Method of Integral Transforms and the Theory of Fredholm Integral equations, that this model leads to bounded stresses and strains, in contrast to the square-root singularities of the stress and strain fields predicted by the classical theory of brittle fracture.