Pouzdani putokaz za certificiranje lijepljenih nosivih konstrukcija

With an increasing pressure to meet unprecedented levels of eco-efficiency, the aircraft industry aims for superlight structures, and, towards this aim, composites are replacing conventional aluminium. The same trend is being followed by the civil, automotive, wind energy, naval and offshore industries, in which the combination of steel and composites, or replacement of steel with composites, can increase the strength-to-weight ratio. However, the joining design is not following this transition. Currently, composites are being assembled using fasteners. This leads to a reduction in load-bearing capacity and is a huge weight penalty for composites, since holes cut through the load carrying fibres and destroy the load path. Adhesive bonding is the most promising joining technology in terms of weight reduction and performance. However, its lack of acceptance is limiting its application to secondary structures, whose failure is not detrimental to structural safety. In primary (load-bearing) structures, fasteners are always included along bondlines, as “back-up” in case the bond fails. The main reasons for this lack of acceptance are the limited knowledge of their key manufacturing parameters, non-destructive inspection techniques, damage tolerance methodology, and reliable diagnosis and prognosis of their structural integrity.
The goal of the Action is to provide a reliable background for the certification of bonded joints in primary (load-bearing) composite structures. Despite the motivation being aircraft structures, which are believed to have the most demanding certification, it will directly involve other application fields in which similar needs are present. This Action will tackle the scientific challenges at the different stages of the life cycle of bonded structures through the synergy of multidisciplinary fields and knowledge transfer.