A semi‐analytical approach for the efficient predicition of thermally induced interface crack initiation at bi‐material free edges

Abstract

AbstractIn the present study, thermally induced interlaminar crack initiation emanating from the free edge of a bi‐material junction is investigated by the example of a uniformly cooled epoxy‐glass bi‐material specimen taken from literature. For this purpose, the coupled stress and energy criterion within the framework of finite fracture mechanics is applied. Interlaminar stresses and energy dissipation due to crack onset are determined efficiently using the semi‐analytical scaled boundary finite element method (SBFEM). Moreover, the effect of the layer thicknesses on crack initiation is studied. For this purpose, dimensional analyses yield simple scaling laws for interlaminar stresses and energy dissipation with respect to the layer thickness such that only few model evaluations are required. The obtained results are compared to a finite element reference solution. For validation purposes, a cohesive zone model is applied additionally. Finally, the obtained predictions are compared to experimental findings from literature.