Modelling the strength of bonded butt-joints

In this paper it is proposed a simple but consistent framework in which to model the mechanical strength of axially loaded aluminium–epoxy butt-joints. The theory accounts for the influence of the load rate as well as the influence of the thickness of the adhesive layer on the strength of the system. Besides it is conceived to give adequate predictions of the rupture force regardless the previous chemical/mechanical surface treatments applied on the bonding surface of the adherend. The material constants that appear in the model equations are simple to be identified experimentally and the resulting mathematical problem is also very simple. Results from experimental testing of various aluminium–epoxy butt-joints have been obtained and compared with model prediction showing a good correlation regardless the kind of rupture (adhesive, cohesive or mixed mode failure).