Hygromechanical analysis of damage in multi-material assemblies: multiscale modeling and characterization – ASHENDO

Many industrial sectors are exploring new materials and processes that offer high performances while reducing their energy footprint and emissions. To this aim, metal/composite structural bonding is of great interest because it guarantees a reduction of on-board weight compared to the traditional techniques, as riveting and bolting, and other advantages such as uniform stress distribution and elimination of galvanic corrosion. Unfortunately, these assemblies are still not extensively used in industries for the lack of understanding and control of the phenomena involving the quality and the durability of the adhesive joint. This research project’s aim is to develop a multiscale modelling strategy for bonded metal/composite assemblies (steel/carbon fibre-reinforced polymers, CFRP) able to predict the damage evolution up to the non-propagation thresholds under the combined action of hygromechanical loads (multi-physics coupling). The proposed methodology is interdisciplinary as it combines analytical modelling, numerical modelling and experimental mechanics. Developed tools will be of great interest for engineers, manufacturers and scientists for the detection of the non-propagation thresholds of initial defects in multi-material bonded assemblies, in service and long duration conditions, in environments with high humidity variations. Part of the project will be dedicated to the built and curatorship of an online open access database that can be interrogated via machine-learning techniques in order to discover correlations between the composition, processing, properties and performance of this kind of assemblies.