Abstract

The development of structural parts optimized in weight and cost has always been a key aspect in the aeronautical industry. Nevertheless, these premises also appears in other industries. A specific study focused on the automative industry showed the possibility of re-studying a technology analyzed in the past: Short Carbon Fiber injection. The technology offered low recurring costs, high rate possibilities and reliable repetitivity of the processes. Based on these statements, aeronautical parts from the Horizontal Tail Plane (THS) with low structural responsibility were defined as target options. After defining the scope, different engineering and manufacturing studies were performed. The conclusions from both investigations, together with weight and cost estimations, confirmed the potential application of the technology for a present and future implementation. The previous project was included in the project FACTORIA, funded by the Ministerio de Economía y Competitividad, by means of the Centro Tecnológico Industrial (CDTI), in the Strategic Programme CIEN 2016.

Abstract

The conception of structural components using thermoplastic composite materials faces a dilemma when selecting the material/manufacturing process pairing. Continuous fiber-reinforced composites offer the best properties, but their design freedom is limited to shell-type parts. On the other hand, manufacturing processes for discontinuous fiber, such as injection (LFT) and forging (GMT), allow the production of complex geometries, but their mechanical properties are substantially lower. In fact, LFT and GMT are important in the current automotive industry, but their applications are limited to semi-structural components or internally complex geometries whose functionality is more focused on function integration rather than supporting high mechanical loads. The hybridization of discontinuous fiber composites with continuous fiber materials presents itself as a promising approach to achieve a synergistic effect from both technologies.

In this study, the impact behavior of glass fiber-reinforced polyamide forged plates (GMT) was characterized, along with their hybridization with unidirectional carbon reinforcements. In the first phase, the effect of the processing temperature was investigated, concluding that increasing the temperature promotes the compaction between the two materials, resulting in improved impact resistance. Specifically, a 14% increase was observed in both maximum force and dissipated energy. In the second phase, the effect of hybridization with unidirectional tapes as reinforcement was analyzed, showing the same positive effect. The hybridization led to a 20% improvement in maximum force and a 36% increase in dissipated energy.