Chopped carbon fiber SMC the focus at Lamborghini; autoclave a technology of the past

With its key performance characteristics being 0-100 kmh and 200 kmh acceleration times and the lap time around Germany's Nürburgring circuit, power-to-weight ratio has always been of primary importance to Italian supercar maker Lamborghini (Sant'Agata Bolognese). The company was one of the first adopters of carbon fiber composites in its vehicles in the 1980s and takes pride in developing all is carbon fiber reinforced plastic (CFRP) components in-house at its Advanced Composite Research Centre (ACRC).

While autoclave-cured thermoset-based composites have played the primary role in lightweighting efforts in past years at Lamborghini, the automaker has always conscious of costs even in the realm of supercars. The company is now actively embracing it lower cost technologies in its latest models, in particular chopped glass fiber sheet molding compound (SMC). Speaking to PlasticsToday at the JEC Asia show in Singapore, ACRC and Body in White (BIW) Structures Engineering Head Luciano De Oto said, "We are moving away from autoclave altogether as we believe it is a technology of the past. Chopped carbon fiber-reinforced SMC is the key technology moving forward for both BIW and aesthetic parts." Lamborghini operates a dedicated  "out-of-clave" development center at its headquarters that is developing SMC, thermoplastic, injection molding and resin transfer molding ( RTM) technologies for its vehicles.

Lamborghini is also a participant in the EU's NewSpec project whose aim is to develop a lower cost process for production of carbon fiber. The EU is contributing EUR7.4 million (about 75% of overall cost) to the project, which brought together a consortium of 13 partners who started work in November 2013. Participants include those from the clean energy, aerospace and oil and gas sectors.

Test production of polyethylene-based carbon fiber at the High Performance Fibre Centre (HPFC) pilot plant facility at the Institute of Textile Technology and Process Engineering (ITV) in Denkendorf (Baden-Württemberg, Germany) has started and will run through to November 2017. The project will then transition to the industrial phase. "A 250-tonnes/year plant will be constructed in 2018, which is enough for our needs," says De Oto. This will be followed by a commercial phase from 2020 with production capacity at the 1000-tonnes/yr level and the technology developed being made accessible to interesting parties subject to patent licensing.

Through to 2030, De Oto expects further cost reductions. "At the moment, a carbon fiber composite component costs five times that of a steel part," he notes. In our aggressive case scenario, CFRP parts will be 67% lower in cost by 2030, with raw material [carbon fiber] cost 50% lower and processing cost 79% lower," he explains. "A more conservative scenario points to an overall reduction of 45%, with material cost 43% lower and processing cost 53% lower." The NewSpec project, meanwhile, targets a 29% lower carbon fiber cost by 2018.

In terms of performance, the NewSpec project targets tensile modulus of 200-250 GPa, tensile strength of 2 GPa, elongation of >1%, fiber diameter of <10 microns, optimal resin wetting and adhesion, and tailored conductivity.