JEC COMPOSITES MAGAZINE - Issue #75 - August/September 2012 - 13

According to BASF, the next major advance in lightweight automotive applications will be achieved through the use of endless fibre-reinforced high-performance composites. Such materials make it possible to develop parts that are very light and strong and provide an efficient way to combine metal, fibre reinforcement and plastic. The newly established lightweight composite team can draw on the company’s knowhow in the areas of polyurethane, epoxy and polyamide chemistry.

Focus

Depending on the customer’s requirement profile, one of these solutions is sure to fit the bill. BASF is devoting significant effort on accelerated curing of the three plastic matrix systems, and thus further shortening the cycle time.

Endless fibres for structural components
Structural chassis or body components can only be manufactured from composite materials reinforced with endless carbon or glass fibres, and require fibre contents of about 65 weight percent. Endless fibres are already used in aircraft and wind power applications, plant construction, prototype construction and short-run automotive applications. Carbon fibres impart very high stiffness as a reinforcing material and are thus of special interest. To interact with application engineers and end users at an early stage, BASF has recently become a member of Carbon Composites e.V. (CCeV), a competence network for carbon fibres and fibre-reinforced composite technology that was established in 2007 and now has more than 120 members. In addition to the performance of a reinforcing material, price and availability are also important for the rapid introduction of matrix systems to the market. Glass fibres show great potential here: the limits of their mechanical strength have not been reached so far.

processable on a reliable basis and readily adoptable for high-volume production. Compared to conventional metal components, these materials will contribute to a weight reduction of about 50%. The new approach is complemented by established technologies used to embed metal inserts or endless fibre-reinforced thermoplastic mats and UD tape (unidirectional fibre reinforcement) in plastics. In addition, endless fibre-reinforced skin layers can be combined with lightweight foam cores to yield high-quality sandwich structures with exceptionally good specific part stiffness and good insulating characteristics in combination with low weight. The PU foam systems developed for such parts are characterized by a high compressive strength and temperature resistance in conjunction with a low density. At the same time, BASF is expanding the capabilities of Ultrasim™, its now universal computer simulation tool, the objective being to be able to predict the behaviour of complex endless fibre-reinforced composites as well.

the glass fibre fabric is embedded, and an impact-modified, short glass fibrereinforced Ultramid which 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 thickness can be reduced considerably, allowing the weight of the seat pan to be lowered distinctly.

Simulation for composite parts
After producing the seat pan for the Opel Insignia OPC from Ultramid in 2008, albeit still without laminate reinforcement, technological cooperation between the two companies went a step further. To design and build the seat pan for the Astra OPC, BASF engineers further provided material descriptions for the virtual design of both the continuous fibre-reinforced laminate and the overmoulded ribbed areas of the part. The knowledge gained from this experience will be incorporated into an extension of the Ultrasim universal simulation tool, making it possible to predict the behaviour of thermoplastic composite parts with continuous fibre reinforcement. The composite seat pan is produced by in-mould forming, that involves placing the heated and formable thermoplastic laminate in the injection mould, turning it into the necessary shape, fixing it cleverly and immediately overmoulding it. BASF supported its customer with its own expertise in this innovative manufacturing process. The seat back, the transverse support and the handle on the back are also made from Ultramid. The seat has 18 adjustment options, allowing optimal adaptation to the body of the driver or passenger. Following numerous other vehicle seats at Opel, the seat for the new Astra OPC also received an award from Aktion Gesunder Rücken e.V. (AGR), the Campaign for Healthy Backs. n
More information: www.basf.de

A world first
The new Opel Astra OPC, a sport coupe which was introduced at the Geneva Auto Show at the beginning of March 2012, has a seat pan made from a thermoplastic laminate with continuous fibre reinforcement (organo sheet). This is the world’s first auto seat pan based on this technology manufactured for a production vehicle. The plastics used are polyamide specialties from BASF’s Ultramid® product range. The seat pan is 45% lighter than its predecessor. Thermoplastic laminates with continuous fibre reinforcement, also called composites, are plastic-impregnated fabrics that are processed into laminates. They serve as the reinforcement in plastic parts that must be especially lightweight yet still exhibit exceptional performance. The company developed two special Ultramid grades for the Opel Astra OPC seat pan: an unreinforced grade which acts as the material in which

Multimaterial systems
The overall system consisting of a plastic matrix and fibre reinforcement must be

No75 August - September 2012 /

jec composites magazine 13

http://www.basf.de

JEC COMPOSITES MAGAZINE - Issue #75 - August/September 2012

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #75 - August/September 2012