Performance evaluation of CFRP/Al fibre metal laminates with different structural characteristics

FMLs (fibre metal laminates) are a kind of hybrid material consisting of composite material layers alternating to metal sheets, that present high mechanical characteristics. The aim of the present work deals with the flexural behaviour of CARALL (carbon fibre-reinforced aluminium laminates) specimens; in fact, the influence of both the layer thickness and the adhesion interface between CFRP layer and aluminium sheets was analysed. Four different laminates, bonded with structural adhesive or with prepreg resin only and with one or two metal sheets (but maintaining the composite/metal volumetric ratio at a constant value), were tested according to the three points bending scheme. The experimental tests evidenced that the flexural strength increased in absence of the adhesive layer and with a single metal sheet. Moreover, some micrographs of the fractured specimens were taken to determine the failure mechanism.