STUDIO NUMERICO-SPERIMENTALE DI GIUNZIONI IBRIDE A DOPPIA SOVRAPPOSIZIONE CFRP-ALLUMINIO

Abstract

The adhesively bonded joints and the mechanical joints between structural components made by composite materials or between elements made by composite and metal, are commonly used in different fields of modern industrial design and manufacturing, since they are characterized by economy, reliability and ease of assembly. The bonded joints are characterized by high stiffness and fatigue life, although delamination phenomena localized near the edges of attack of the adherends may limit their use, especially in particular applications where corrosive environments and humidity can lead to premature failure. In these cases, a possible alternative is offered by the well known riveted joints. On the contrary, the riveted joints require a preliminary drilling of the elements to be joined and, consequently, may cause localized material damage, especially in presence of strongly anisotropic laminates which are characterized by high stress concentration. In the present work a numerical and experimental study of hybrid double-lap joints between aluminum and CFRP laminates, have permitted to highlight both the static and the fatigue performance of such joints, also with reference to the particular damage mechanism of the adhesive layer and to the interlaminar damage of the CFRP, due to the riveting process.