Abstract

One of the main "drivers" in the development of aeronautical structures in composite material is the development of more integrated structures that are manufactured in a single step ("One-Shot") to optimize times. The adhesive materials in film format are one of the main variables to take into consideration to achieve the aforementioned integration. This need has promoted creativity at the level of use / parameterization of new adhesives in the form of a film.

Film adhesives are used in the integration of composite, sandwich or monolithic structures. Regarding sandwich structures, the adhesive film is used to ensure a good adhesion between the core and the prepreg, through the formation of a meniscus of adhesive material in the core cell. This function is fulfilled depending on the type of "carrier". For Monolithic structures, the adhesive film is used to ensure a good adhesion in co-bonding processes (bonding of cured laminate with fresh prepreg) and secondary bonding (bonding between 2 previously cured laminates), interleaved between materials to achieve optimum thickness, guaranteeing the best mechanical properties of the element at interlaminar level. This, without forgetting, the repair processes that are within the processes of co-bonding, with all its specificities and operational limitations, either in manufacturing or in service.

The market options, qualified by OEMs or not, are wide, having developed different support materials, or variants of the same material, with the aim of achieving the best mechanical properties of the elements where they are used.