Issue 51

C. Bellini et alii, Frattura ed Integrità Strutturale, 51 (2020) 442-448; DOI: 10.3221/IGF-ESIS.51.32 447 C ONCLUSIONS LMs are hybrid laminates, constituted by metal sheets and composite material layers interposed, that present high structural properties. However, the reliability of the interface between metal and composite is very important; for this reason, the influence of the metal/composite interface and the stacking sequence on the ILSS (interlaminar shear strength) was investigated in the present work. In particular, for the first factor the bonding agent consisted in a structural adhesive or the resin of the prepreg itself, while, for the second factor, the number of metal sheets was varied: a single sheet or two ones were considered, maintaining at a constant value the volume ratio between carbon fibre and aluminium, in order to obtain different layer thickness. The ILSS was chosen as parameter to be studied since it relied on the interface effectiveness, and it was determined through the three-point bending test on short beam. Three types of specimens were produced and tested: the first one with a single metal sheet bonded with adhesive, the second one with a single metal sheet bonded with prepreg resin and the third one with two aluminium sheets bonded with adhesive. The experimental tests found that the laminate showing the highest ILSS was the first one, while the second one presented the lowest value. Moreover, a statistical analysis was performed on the experimental results for stating the influence level of the different factors, and it was discovered that the layer thickness had a low effect on the shear strength, while the interface typology was the most influencing factor. The work was completed with the analysis of the shear stress trend as a function of the loading nose displacement. 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