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The extension of the vacuum-assisted multipoint moulding (VAMM) technology to a broader field of geometries makes it necessary to extend it with attachments to the enhanced vacuum-assisted multipoint moulding with additive attachments (EMMA) technology. Therefore, it is necessary to build additive manufactured attachments on a curved silicone surface by fused filament fabrication (FFF). The main challenge of FFF on a silicone-made build plate is the adhesion of the part on the build plate. Hence, the purpose of this paper is to find suitable and reliably manufacturable material and adhesion promoter combinations for the use of the FFF on silicone build plates.

The combinations of seven different filaments and four adhesion promoters were investigated with an experimental study. Therefore, four different specimen geometries were built with the different combinations and tested in a tensile test, and some of the specimens were analysed with a confocal laser scanning microscope (CLSM).

This study proves that the FFF on unheated silicone building plates is possible for several material combinations. As a filament material, polylactide can reliably be manufactured with all of the investigated adhesion promoters on the silicone build plate. Thereby, the highest adhesion strengths were achieved with an adhesive foil as an adhesion promoter, whereas the glue stick is the most appropriate solution. The investigations with the CLSM showed that there are large differences in the manifestation of the first layer depending on the adhesion promoter used.

To the best of the authors’ knowledge, this study is the first to demonstrate the manufacturing of FFF-made attachments on silicone build plates for the EMMA process. This paper provides measurement data on the build plate adhesion of the attachments on silicone-made build plates.

Aircraft wings, one of the most important parts of an aircraft, have seen changes in its topological and design arrangement of both the internal structures and external shape during the past decades. This study, a numerical, aims to minimize the weight of multilaminate composite aerospace structures using multiobjective optimization.

The methodology started with the determination of the requirements, both imposed by the certifying authority and those inherent to the light, aerobatic, simple, economic and robust (LASER) project. After defining the requirements, the loads that the aircraft would be subjected to during its operation were defined from the flight envelope considering finite element analysis. The design vector consists of material choice for each laminate of the structure (20 in total), ply number and lay-up sequence (respecting the manufacturing rules) and main spar position to obtain a lightweight and cheap structure, respecting the restrictions of stress, margins of safety, displacements and buckling.

The results obtained indicated a predominance of the use of carbon fiber. The predominant orientation found on the main spar flange was 0° with its location at 28% of the local chord, in the secondary and main web were ±45°, the skins also had the main orientation at ±45°.

The key innovations in this paper include the evaluation, development and optimization of a laminated composite structure applied to a LASER aircraft wings considering both structural performance and manufacturing costs in multiobjetive optimization. This paper is one of the most advanced investigations performed to composite LASER aircraft.