|Faced with growing concerns about the impact that automobiles have on the environment, Original Equipment Manufacturers (OEMs) are facing a new reality: the drive to dramatically reduce fuel consumption and Carbon Dioxide (CO2) emissions. While alternative fuels are still in a nascent phase of development, the automotive industry must quickly look to other solutions which aid in the effort of environmental protection. The result is the burgeoning of a new trend to embrace the use of lighter weight materials that will replace heavier, less eco-friendly metal components and parts. In Europe, studies have shown that plastics materials as an alternative to metal helps to decrease fuel consumption in European cars by 750 litres over a life span of 150,000 kms. This alone suggests a sharp improvement in the volume of our CO2 emissions, as per Borealis. More importantly, the amount of plastics materials required is significantly less than its metal counterparts: only 100 kilograms of plastics are needed to replace 200-300 kilograms of conventional material. Metal replacement holds the potential to cut our oil consumption by 12 mln tons and implies an annual reduction in our CO2 emissions by 30 mln tons in Western Europe alone. This is strongly suggestive of the industry�s need to integrate more plastics materials in their automotive designs.
Currently in the automotive industry, polypropylene (PP) is the most widely used thermoplastic compound, delivering durable solutions to a range of end applications. Borealis has taken the lead in this rapidly evolving trend by developing new, innovative resins that serve a spectrum of automotive components and parts, including Bumpers, Fenders, and Body panels.
Borealis has been successful in developing superior performance materials that fit with novel types of conversion processes and has actively been involved in advanced simulation and creative concept designs. In consequence, the entire value chain benefits from lower weight solutions that ultimately help curb CO2 emissions and fuel consumption. New developments include:
BMW X5 Fender: The fender was traditionally produced with steel but is now manufactured with our Daplen TPO Compound. This has enabled a 50% weight reduction in the fender. The compound also adheres to safety requirements of EuroNCAP 2010.
Front Bumper and Front Truck Body Panel: These parts that have been produced using Sheet Mould Compounds (SMC), an unsaturated Polyester thermoset, was replaced by our light weight solution of Daplen TPO Compounds for the aesthetic parts, and our robust Nepol LGF compounds for structural carriers. This PP solution has resulted in an overall 35 % weight reduction in the final part and a significant cost-savings in production.
Smart Exterior Body Panels: These body panels were produced using polybutylene-terephthalate (PBT)/polycarbonate (PC) blends, and our High performance Daplen TPO Compounds, lead to an overall 20% decrease in the weight of the panels. In addition, the material provides superior flow-ability that reduces the thickness of the final part by 10%.
Lowering density without compromising performance: In addressing the global challenge of cutting our CO2 emissions, Borealis has also developed lower density materials that help decrease the weight of automotive components and parts, without inhibiting their ability to fulfil performance requirements. Borcom Micro-composites are materials that are even less dense than consolidated PP compounds, representing a new generation of materials capable of lowering the weight of heavier components and parts like bumpers and climate control housing units. Breakthroughs in single-material solutions taking the spotlight include:
• All-PP rear-seat carrier - An all-Xmod solution is replacing a polyurethane and steel hybrid previously used by a major European car maker. The new design, in a model due to be launched later this year, is 35% lighter than its predecessor, taking around 4 kg off the weight of the car. The concept should also yield significant cost savings in production, thanks to a simplified molding manufacturing process.
• Skoda Fabia interior - The interior quality and visual appeal of the new Skoda Fabia are enhanced with the use of three different Daplen PP grades, for the dashboard, visible structural parts integrated into the dashboard, and door panels - as well as for the trunk cladding. Scratch resistance, a balance of stiffness and impact strength, thermal expansion, gloss, emissions, odour and fogging were all key issues that had to be tackled in the development of the parts. To cope with cost pressures, moulders also focused strongly on processability and reduced scrap rates.
• Smart fortwo body panels - The second generation of this ground-breaking Daimler Group car is the first production vehicle in the world to have all vertical body panels manufactured from PP. Borealis developed Daplen ED230HP to meet Smart's targets for improved environmental performance and higher quality aesthetics compared with the original version. The six injection moulded PP exterior body panels (front end, rear end, bonnet, tailgate, doors) contribute to an overall weight reduction in the car of 15 percent. They also provide a better fit and finish, with reduced gap between parts and higher surface quality, as well as an excellent impact/stiffness ratio.
• Audi TT bumpers - The front and rear bumpers of Audi's new TT are made from Daplen ED223AE, a 20 % mineral and elastomer modified PP compound for injection moulding with an excellent impact/stiffness ratio. The superb surface aesthetics, very low CLTE thermal expansion values and excellent paint adherence were among the other key determinants in choosing this material.
DSM helps optimize system costs and shorten time-to-market by combining application knowledge with development capabilities.
• Akulon Ultraflow has 80% better flow than normal polyamides allowing for faster cycles and thinner walls � ideal for engine covers and intake manifolds.
• Arnitel provides easier processing, lower fill pressures, faster cycling, and greater design flexibility for airducts through its better flow characteristics.
• Akulon ES enables electrostatic powder coating in a single primerless step, lowering costs and environmental load in automotive roof racks.
• Stanyl offers shorter cycle times and better processing for wear and heat resistant engine, transmission and electrical components.
• Akulon Ultraflow gives a superior finish to reinforced nylon parts like engine covers that can eliminate after-treatments and reduce system costs.
• Arnitel PL471 has excellent adhesion to PC and polyester based materials, enabling 2K molding processes that reduce or eliminate visible joins or weld lines, improving surface finish for airbag covers.
• Stanyl high modulus grades extend the scope for metal replacement in applications like chain tensioners at temperatures up to 200°C (390°F).
• Gears in Stanyl transmit higher torque at smaller sizes; replacing metal gears with redesigned components that reduce overall costs.
• Using Arnitel in ducting integrates part functionality with lower fabrication costs and easier assembly.
• Akulon grades are as easy to mold as standard resins but with higher stiffness for metal applications.
High-Performance VICTREX® PEEKTM has replace metals in a range of applications to meet demands for weight reductions and system cost savings. The polymer, a member of the polyaryletherketone (PAEK) family, is a linear, aromatic, semi-crystalline polymer widely regarded as one of the highest performing thermoplastics in the world. In recent years, high-performance The polymer has been successfully used as a metal replacement in a range of industries and applications. The polymer may effectively replace titanium, magnesium, brass, corrosion-resistant (CRES) or stainless steel and specialty alloys due to its unique combination of mechanical, thermal and tribological properties, combined with excellent chemical resistance and electrical performance. In addition, the polymer can be used as a matrix for thermoplastic composite prepregs reinforced with carbon, glass or aramid continuous fibers. Several new grades and compounds are available to maximize mechanical properties and moldability, as well as to provide processing flexibility. Material developments at Victrex Polymer Solutions have included the addition of VICTREX® PEEKTM 90 grades to the existing 150, 380 and 450 polymer grades. The 90 family of grades are primarily aimed at applications where high flow is required. Each of these is available in filled compounds which allow for high levels of filler incorporation without any loss in processability. Structural fillers include chopped glass fiber (GL grades), chopped carbon fiber (CA grades), and special high modulus carbon fibers (HMF). The 90HMF grades offer significantly increased tensile strength and modulus compared to standard carbon fiber compounds. Higher temperature requirements have driven further innovation at the molecular level to create VICTREX HTTM polymer and VICTREX STTM polymer. These products provide improved mechanical performance at 15°C to 25°C higher temperatures while maintaining the excellent balance of properties of this polymer. These higher temperature platforms are also available in glass and carbon reinforced compounds for structural applications. The advantages that polymers have over metals include:
• High temperature performance
• Weight reduction
• Fatigue performance
• Wear resistance
• Chemical resistance
• Hydrolysis resistance
• Fire, smoke and toxicity performance
• Electrical properties
• Noise reduction
• Vibration dampening
Automotive industry manufacturers are constantly looking for ways to reduce noise and vibration as well as improve efficiency. Metaldyne has achieved both in their balance shaft module product line made with VICTREX PEEK polymer.Balance shaft modules are used to cancel the inherent shaking forces associated with in-line 4 cylinder engines. As an industry leader in balance shaft and balance shaft module design, Metaldyne co-developed gears molded from this polymer for their balance shaft modules. VICTREX PEEK polymer was chosen for its excellent fatigue strength, chemical resistance, high temperature resistance and strength at elevated temperature. The innovative design minimizes mass, rotational inertia, and NVH (noise, vibration and harshness). Manufacturers of check valves and pressure relief valves for hydraulic and pneumatic compressors are constantly looking for ways to improve the performance of their products. Valve performance, more than any other component, determines compressor efficiency. To achieve improvements such as reduced fluid leakage, noise reduction, longer valve life, and cost reduction, a number of manufacturers are turning to Performance Plastics Ltd., a high performance injection molding specialist, for assistance. To meet the requirements, PPL suggests replacing the metal poppets in the valves with poppets made of VICTREX PEEK a high performance thermoplastic. Substituting plastic for metal maintains strength while improving corrosion resistance, reducing weight, and allowing for greater design flexibility. The automotive industry faces increasing pressure to maximize performance while minimizing weight and cost. Additional considerations include noise abatement, more electronics components, new safety standards, and the environment. The polymer is lightweight and offers excellent mechanical performance at high temperatures. It can successfully replace metals and other polymers due to its unique combination of outstanding wear performance, processing flexibility, and excellent chemical resistance, including all automotive fluids. The polymer is featured in many transportation applications such a piston units, seals, washers, bearings, transmission, braking and air-conditioning systems, actuators, gears and electronics/sensors. Parts made of this high performance polymer can be manufactured using a wide range of melt processes including coatings and films.
The BASF Innovative Technology Group�s approach to automotive seating systems viewed its challenge in terms of systems, not merely part-for-part substitution. In one seating application, replacing metal with a BASF plastic seating system produced 15 fewer parts, 10 fewer assembly steps and reduced weight by 6.5 lbs. compared with the previous metal seating components. When BASF plastics consolidate parts, they lower both system and assembly costs. BASF�s Ultramid® nylon, Petra® PET and Nypel® recycled nylon materials are hard at work in several automotive seating systems, including seat cushion and back frames, seat track adjusters and transmissions, lumbar handles and supports, as well as recliner handles. BASF developed Ultramid® TG resins to meet the exacting requirements of the first North American metal replacement application for an automotive seat cushion pan frame. Components made of Ultramid® and Ultrason® are lightweight and resistant to high temperatures and engine oils. They feature high mechanical strength and stiffness, and in contrast to metal components do not corrode. The high freedom of design also makes it easy to integrate additional functions.
DuPont�s grades of Zytel PLUS, a family of polyamide products with improved durability that can double the life of thermoplastic components exposed to hot, chemically aggressive and humid environments. Some of the following applications may use these new grades of polyamides include air coolers, turbo air ducts, Engine mounts, cylinder head covers. oil pans. transmission parts
SABIC Innovative Plastics has introduced STAMAX long fibreglass PP composite used in floor consoles and instrument panels. The benefits of STAMAX grades are
• 15 % cost saving
• 20% lower weight
• Improved surface finish compared to short fibreglass
DuPont Automotive is developing engineering plastics and new high-performance composite materials that provide improved function in automotive applications at weight savings of 30-40% over metal components. At the same time, the materials can provide cost savings of 30-50% by integrating separate parts into modules. New materials can withstand heat in the engine compartment up to 260°C (500°F), expanding the possibilities for metal replacement. They also enable moulded-in fittings for fast assembly and better packaging in cramped engine compartments, notes the manufacturer.
Lanxess reports advances in its family of reinforced semi-crystalline products toward the goal of replacing metal automotive components, including frames and other structural parts. The company offers Durethan® polyamides and Pocan® polyesters with high glass fibre reinforcement levels of 50-60% which can be processed as easily as a general-purpose grade with 30% reinforcement, the company says.