Closed-form analysis of crack initiation in layered systems under thermal loading

In this work a closed-form analytical model of a two-layer system is analyzed. Therefor a higher-order displacement approach, which takes the singularity order into account is used to approximate the displacements and the strain and stress field within these two linear elastic layers. For three configurations – a patch on a substrate under thermal loading, a Double Cantilever Beam and a Single Lap Joint under mechanical loading – the interlaminar stresses at the interface between both layers are discussed. The configuration of a patch on a substrate under thermal loading is analyzed in more detail. Here, within the framework of Finite Fracture Mechanics also the initiation of a debonding crack is also investigated. All results are compared to a Finite Element Model for validation.