Dynamic behaviour of composite adhesive joints for the automotive industry

The automotive industry has significantly increased the use of adhesive joints in vehicle construction, which can be explained in part by the widespread adoption of composite materials and structures. The combined use of composites and bonding allows the manufacture of structures with high mechanical strength and reduced weight. However, to ensure vehicle safety, these adhesive joints must be able to sustain large impact loads, transmitting the load to the structure without damaging the joint. This work aims to study the impact behaviour of composite adhesive joints bonded with a ductile epoxy adhesive, comparing different overlap lengths. For this purpose, a characterization of the behaviour of single lap joints was performed under quasi-static and impact conditions. Dynamic tests were also performed using vibration analysis to assess the damping capabilities of the studied joints. Numerical models were developed with cohesive elements in ABAQUS® software, including both quasi-static and dynamic models. It was demonstrated that joints manufactured with this type of adhesives and substrates can exhibit excellent impact strength and damping capabilities. It was also shown that the behaviour of these joints can be successfully modelled using static and dynamic finite element analysis.