Flexural mechanical properties of bonded-overlaminated GFRP-aluminium butt joints

In this work, a bonded composite-aluminium butt joint, used for marine applications, was investigated. In order to exploit the advantages of adhesion (i.e. reduction of local delamination due to the absence of holes, significant reduction of the weight and cost of the structures, prevention of degradation phenomena in consequence of galvanic corrosion and high absorption of energy), by increasing its properties, an overlamination sequence was applied. It consists of overlapping layers made of fibreglass reinforced resin to form a large patch fitted for the joint profile. In particular, four joint configurations were investigated, considering at first the behaviour of butt joints both with only adhesive and only overlamination, and then, with the combination between adhesive and overlamination in the other joints. Analysing all results, the better outcomes were obtained by the joint configuration which has a layer of adhesive between the two substrates end-faces and the overlamination.