Failure analysis of adhesively bonded joints in composite materials

The present paper is concerned with a phenomenological model to perform the failure analysis of composite adhesive single lap joints with arbitrary glued area. The theory is conceived for joints composed by highly resistant elastic adherends bonded with brittle–elastic adhesives. It is shown that, under certain conditions, the rupture forces (in the case of monotonic loading) and lifetimes (in the case of cyclic loading) of two joints with different glued areas can be correlated using a shape factor. Results from experimental static and fatigue testing of joints with carbon/epoxy laminates bonded with epoxy adhesive and different bonding areas are compared with model prediction showing a good agreement.

► We propose a phenomenological model for the failure analysis of bonded joints in composite materials.
► It allows correlating the static and fatigue strength of two single lap joints with different geometries.
► The model is valid for brittle-elastic adhesives and highly resistant composite adherends.
► Carbon/epoxy laminates bonded with epoxy adhesive are considered in the study.
► Model predictions are compared with experimental results showing a good agreement.