New resins make a play in the automotive market Lightweight plastics like composites are becoming a feature, while sustainable materials from recycled resins and renewable raw materials are being used by vehicle makers to further improvements to lower weight and carbon emissions. Nevertheless, Plath said an immediate task is to reduce the costs of CRFP by 50%, processing costs by 90%, cost of painting CRFPs by 70% and most importantly to reduce CO2 emissions over the entire life cycle of the CRFP materials themselves by around 55%. Currently, producing 1 kg of carbon fibre emits 40 kg of CO2 and Plath said the carbon fibre industry has to look at improving production efficiency by using alternative heating technologies like plasma or microwaves and to consider alternative raw materials such as lignin. Rounding up, Plath sees a mix of steel, aluminium, magnesium, CRFP and other reinforced plastics, such as those employing long glass fibres, to most likely offer a financially lucrative solution. “It will be some time before we are able to achieve sustainable lightweighting,” he concluded during his presentation at JEC.
Composites shaping up while costs still an issue German supplier Lanxess’s lightweight offerings include long glass fibre-reinforced nylon composite sheets, into which it has invested heavily on the development of simulation methods and the determination of characteristic material values to component testing. The company says this is a prerequisite for achieving high-strength, lightweight nylon composite hybrid structural components, such as car sills and B pillars, in a subsequent injection moulding stage using polyamide (PA). It also expects the composite technology to be a cost-effective alternative to carbon fibre-reinforced thermoset components. German compatriot BASF is also into glass fibre grades having recently introduced three crash-optimised PA6s reinforced with 15-50% glass fibres. The company tested out the materials on a structure with a 45-degree ribbing. The Eiffel Towerlike test specimen makes it possible to investigate materials in special load situations. When clamped in a torsion test fixture, the part withstands static torsion of over 240 degrees, says BASF. Initially targeted for body applications intended to provide pedestrian protection, these plastics are also suitable for other crashCalling its new test specimen the Eiffel Tower, BASF used it to relevant components such develop three new crash-optimised as the steering wheel, as PA6 grades in the CR family structural inserts or on the seats: wherever fast absorption of high amounts of energy is required. Meanwhile, vehicle maker Volkswagen, which expects to be the world’s second largest automotive maker in terms of output this year after General Motors, is featuring carbon fibre-reinforced (CRF) composites in its high end vehicles, said Armin Plath, Head of Materials Research and Manufacturing Processes. When asked about the high costs associated with CRFP, Plath told PRA during the recent JEC composites show in Singapore that cost is not an issue since the material is used in the high end range of Bugatti Grand Sport, Audi R8 Spyder, Lamborghini Aventador and Bentley Mulsanne vehicles.
Electric vehicles – flame retardants and lighter parts The use of flame-retardant plastics in electric cars is expected to increase, according to Lanxess, due to the high currents and voltages in the area of the batteries and drives. At the recent Fakuma exhibition in Germany, Lanxess showcased a battery disconnect unit that cuts the flow At the Fakuma, of current Lanxess showcased from the what is said to battery to be the largest ever the electric truck engine oil pans motor in the made of PA6 and 66, used in the 12.8 l Euro event of a crash. 6 engines for the Mercedes This unit is made Actros trucks from Daimler of a low-distortion, reinforced flame-retardant Durethan PA6 grade. A control unit made of Pocan B 4235 polybutylene terephthalate (PBT) for automatic start-stop systems in cars was also on show. Another German supplier Bayer MaterialScience (BMS)’s contribution to lighweighting in electric vehicles is a 20 kg-roof module with glazing and integrated solar modules developed as a prototype component and concept study by Webasto. The roof module’s low weight is thanks largely to the lightweight panoramic panel, which consists of BMS’s transparent Makrolon PC developed for automotive glazing. Meanwhile, the company is also propagating the use of PC for other components. In an environmental study by an 1
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Automotive Industry independent consultancy firm using the example of a mid-class car, it was found that if all a car’s glazing with the exception of the windshield were made of PC (a total of 15 kg of the plastic), the lower fuel consumption could cut CO2 emissions by up to 330 kg/vehicle over a vehicle’s service life of 150,000 km compared to cases where glass is used. Greening through recycled and sustainable material Another way to reduce carbon emissions is through a “green” blend of polycarbonate and polyethylene terephthalate (PC+PET) offered by BMS for horizontal automobile bodywork parts. The Makroblend material is manufactured from post-consumer and post-industrial recyclates. The new material blend is particularly well suited as a substitute for sheet mould compounds (SMC), sheet steel and aluminium in bodywork applications, such as spoilers, trunk lids and skirts as well as covers for antennas and convertible top compartments. With large production runs, it is significantly more economical because it yields moulded parts that require no reworking and that can be coated without pretreatment to produce components with Class A surfaces, says BMS. Furthermore, its lower density means that it harbours potential for saving weight. Its primary advantages over metals lie in the design flexibility and the potential for reducing costs through functional integration. UK-based technical plastics company, Luxus has developed a new lightweight PP compound that claims to significantly lower the weight of the average car and potentially reduce CO2 emissions by 520,000 tonnes/year. Developed to replace standard talc filled grades for car interior components, it is said to offer reduced filler content of just 10%, as opposed to a typical 25%. The company claims the new PP compound will enable it to achieve much lower weight vehicle components, without compromising on, performance and design flexibility. It is also made from up to 60% recycled content which means it offers a more sustainable choice too. Luxus said manufacturers will be able to achieve a weight reduction of typically 20 kg per car. For example, for a mid-sized family car this weight reduction could lower CO 2 emissions by 2 gm per 100 km travelled. The company is piloting the new polymer with a number of major car manufacturers before it goes into general production on current models. Italian automotive components supplier Hutchinson, a member of Total Group, has launched a fuel line for diesel engines that uses US firm DuPont’s bio-based plastic blend, making it 20% lighter than metal ones. Zytel PA1010’s content is 60% based on castor oil-derived sebacic acid. The material is extruded into a fuel line used on Fiat cars including the Fiat 500, Panda, Punto, Lancia Ypsilon and other vehicles using diesel or biodiesel fuels. Biodiesel fuels are more chemically aggressive than standard diesel and also have to withstand to temperature and mechanical stresses required in other fuel lines. In its testing, Hutchinson says it found that the PA1010 grade was able to withstand the requirements better than a competitive PA12 material. Hutchinson said it will extend the use of the material to other vehicles and in other fuel system applications. ◆ Fuel lines used with both diesel and biodiesel are produced using DuPont’s renewably-sourced Zytel nylon by fluid transfer system supplier Hutchinson and debut on all new turbo and multijet diesel engines used on several Fiat vehicles
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IMA Automotive 2011 December