Lightweight rear seat shell in composite design
TEPEX continuous-fibre-reinforced composites from Lanxess are becoming established in large-scale production of various structural components for lightweight automotive design. One current example of this is the Audi A8. This sedan car is also offered with two electrically adjustable individual rear seats, the shells of which have been developed by Faurecia Automotive Seating and are manufactured using the hybrid moulding process. The polyamide-6-based Tepex dynalite 102‑RG600(2)/47% is used for this purpose. The short-glass-fibre-reinforced Durethan BKV30H2.0 polyamide 6, also from Lanxess, is used as an over-moulded material.
The composite material is around 45% lighter than a comparable metal design but can also be produced cost-effectively, thanks to the high degree of functional integration. It can also withstand the high mechanical loads in a crash.
Up to now, comparable seats have mainly been made using metal shells screwed onto a substructure. Manufacturing the metal shells is time-consuming as they consist of numerous individual parts that have to be joined together by means of welding in several steps. In the hybrid moulding process, by contrast, a ready-to-install component is created in a single process step. The pre-contoured and heated semi-finished composite product is formed directly in the injection moulding tool for this purpose, and equipped with numerous functions by means of injection moulding.
In addition to reinforced ribs, the piping groove for securing the seat cover in place as well as numerous holders and guides (e.g. for seat ventilation and cable holders) are integrated into the component. The clips to attach the seat shell are also directly injected. The shell can be assembled easily and quickly without screws using the clips, and disassembled again for servicing purposes. The clips are highly stable and meet all relevant safety requirements.