JEC COMPOSITES MAGAZINE - Issue #74 - July 2012 - 27

Fig. 3: Overmolding of CFR structures with GF thermoplastics can take different forms

component properties very effectively through the nearly limitless choice of layer constructions and the associated fibre orientations. In both cases, the prepregs are thermoformed to three-dimensional shapes. Then, they are injection overmoulded, for example with a glass fibre reinforced polyamide, to produce hybrid components with high stiffness and strength. A seat back developed jointly by BASF and Faurecia is close to mass production (Fig. 4).

The seat pan for the new Opel Astra OPC is the world’s first mass-produced car seat pan based on thermoplastic laminates with a continuous fibre reinforcement (Fig. 5). The plastics used are two different polyamide specialties from BASF’s Ultramid® product range. An unreinforced grade acts as the material in which the glass-fibre fabric is embedded, and an impact-modified, short glass fibre reinforced Ultramid is used as overmoulding material to achieve the necessary ribs and edges by means of classical injection moulding. Thanks to the high strength of the laminate, the wall thicknesses can be reduced considerably, allowing the weight of the seat pan to be lowered by 45% compared to its predecessor. In terms of process technology, overmoulding of the pre-formed laminate fibre structure offers all the advantages of thermoplastic injection moulding, such as short cycle times, high levels of automation, reproducibility, modularity, functional integration and recyclability. Thermoplastic laminates utilize their strengths as 2D components: they are used as semi-finished products and are thermally formable either during or shortly before the overmoulding step.

Fig. 6: Steel cord fabrics

Fig. 4: The seat from Faurecia and BASF: Continuous fiber tapes in the seat back (white) overmolded with PA (black): 20% weight reduction

Injection moulding and steelcord reinforcement
Another novel technology is currently being developed: together with its partners Bekaert (Belgium) and voestalpine Plastics Solutions (Netherlands), BASF is now working on the development of thermoplastic components that are reinforced with steel cord fabrics and produced by means of injection moulding (Fig. 6). The three companies have joined together with the objective of using and further developing the new EASI (Energy Absorption, Safety and Integrity) technology with partners in the automotive industry. The steel cord reinforcement employed in the EASI concept ensures that an injection-moulded part retains its structural integrity. Thus, while the parts may be damaged in a crash, they are still able to absorb energy and

lead it further into the structure. This is a decisive innovation when compared to moulded plastic parts with conventional reinforcement that usually fracture upon failure. The material is thus predestined for regions that are intended for absorption and harmonic distribution of crash energy (see video: www.plasticsportal. eu/ultramid-steelcord). For this purpose, BASF is continuing to develop its crashoptimized short or long fibre reinforced polyamide specialties in the Ultramid® product line for use in combination with the steel cord inserts. By using polyamide as matrix material, it is not only possible to access attached or semi-structural parts, but also gain entry to components of the body-in-white (BIW), which need to run through the e-coating process. The resulting level of performance cannot be attained with other types of reinforcing technology. Vehicle components where these characteristics can be exploited include structure-relevant attachments such as bumper beam carriers or front ends, as well as BIW components. All of these innovative continuous fibre reinforcement technologies aiming at early and high-volume serial production have tried to incorporate injection moulding as their basic process because this is the established, highly automated plas-

Feature Automotive

Fig. 5: The Opel Astra OPC composite seat pan: Weight reduction: 45%

No74 July 2012 /

jec composites magazine 27

http://www.plasticsportal.eu/ultramid-steelcord http://www.plasticsportal.eu/ultramid-steelcord

JEC COMPOSITES MAGAZINE - Issue #74 - July 2012

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #74 - July 2012