Polymer composite materials in automotive industry - Coursework Example

Polymer composite materials in automotive industry The use of polymer composite materials in automotive industry has been part of this industry since 1953. The Carbon fibre composite materials have been in used in applications with low production volumes, because of their shortened lead times and lower investment costs relative to conventional steel fabrication. The important drivers of the growth of polymer composites have been the reduced weight and parts consolidation opportunities the material offers, as well as design flexibility, corrosion resistance, material anisotropy, and mechanical properties. (Bunsell, 1998) One of the advantages of carbon fibre composite materials that makes them dominant for use in the automotive industry is because they are light weight. The carbon fibre composite materials have an unsurpassed strength-to-weight ratio and low weight that is essential for the automotive industry. For instance, the manufactures of race cars use carbon fibre composite materials hence they have developed ways of giving this carbon fibre pieces strength in a particular direction i.e. ensuring it is strong in direction bearing the load while weak in directions where little or no load is concentrated in the car. The current trend of materials in car industry of replacing metal parts more and more by polymer composites is aimed at improving the fuel economy and reduce the weight of the vehicles. (David, 2007) There has been increased use of carbon fibre composite materials in the automotive industry because of their cost. The cost of a new material is always compared to that presently employed in a product, hence making it one of the most important variables that determines whether any new material has an opportunity to be selected for a vehicle component. When we talk of the cost of the carbon fibre composite materials, it refers to actual cost of raw materials, manufacturing value added, and the cost to design and test the product. In terms of cost, the carbon fibre composite materials are relatively cheaper as compared to other materials such as cast irons, steel, cast aluminum and magnesium hence their continued use in the automotive industry. (Hilado, 1994) Lastly, carbon fibre composite materials are increasingly being used in the automotive industry because of their safety implications and crashworthiness. The crashworthiness refers to the ability to absorb impact energy and be survivable for the passengers. Therefore, the two important safety concepts in automotive industry to consider, crashworthiness and penetration resistance. Therefore an effective material should have the potential of absorption of energy through controlled failure modes and mechanisms that provides a gradual decay in the load profile during absorption. Carbon fibre composites are generally characterized by a brittle rather than ductile response to load. Therefore the geometrical and dimensional aspects have a key role in different stages of crash hence making carbon fibre composites appropriate for use in manufacture of these vehicles. (Rapra, 2010) Question 1 (b) The debut of the hood and roof commercially is a very important step in automotive carbon fibre composite materials. Currently, carbon fibre composite materials are the strongest and lightest materials in the automotive construction industry. The manufacturers acknowledge the carbon fibre composite materials offer an ideal means of reducing the mass of the vehicles without the sacrificing the safety of the vehicles. However, relative high cost of carbon fibre composite materials, the time required in processing, the high expenses incurred in the processing of autoclave and inadequate predictive-engineering tools have led to only a few manufacturers embark on mass production of high-end vehicles using carbon fibre composite materials. (Pimenta & Pinho, 2011) In the low volume production, the autoclave processing is fast enough to supply the parts required for the production. In order to recover the expense of manufacturing the super-premium materials, the retail price of manufacturers is set high enough. However, in the manufacturing of many units of automotives, the cure for autoclave is slow and expensive hence need to find resins that cure the autoclave faster and also develop new processing derivatives i.e. out-of-autoclave process. The makeover variables can be minimized using the same resin, the laminate technology, structural adhesive and clear coat chemistry. The adhesive is varied through heating while it’s applied robotically and parts fixture for cure at a certain temperature. (Malnati, 2013) During the massive production, both the roof and the hood are molded on a globe pressure with patterns fitted. However, there is no economic advantage in terms of cost in manufacturing smaller automotives due to a lower energy consumption using carbon fibre composites. The molding process can be maximized by hand laying each part on an indexing table and using a prepreg from a kit produced robotically in another part of the facility. However, there is no technology to support an automated lay up of geometric parts with the compound sweeps found in automotives. There is also need for conjunction with resin and prepreg producers since the molding of the equipment may not be possible in keeping up with fast-cure resin systems. Therefore, the use of carbon fibre composite materials are appropriate for low production volumes in the manufacture of body panels. It is uneconomical for mass production due to long processing time and high costs incurred. (Caspe, Day, Wilkinson, & University of Manchester, 2010) Question 2 In as much as the carbon fibre composite materials is advantageous to the manufacture of automotives, most manufactures are moving away from the use of these carbon fibre materials. Carbon-fiber-reinforced plastic (CFRP) technology is considered the most appropriate technology for manufacture of these vehicles due to its strength and weighs less. However, there are difficulties for its use in automated mass production due to its high price and long processing times. For instance, Ferrari has shifted from the use of carbon- fiber-reinforced plastic (CFRP) technology to the use of aluminum. (Carney, 2011) Other companies such as BMW and McLaren Automotive have decided to sell their models built in carbon- fiber models. This is basically due to the fact that manufacturers have found production of cars using other materials such as aluminum can produce more cars per day i.e. 30 cars since its production does not include the use of labor and time-intensive pre-impregnated carbon fiber. It only employs the method of injecting resin into a cloth placed into a mold; a process that normally takes a shorter time as compared to the preparation of carbon-fiber-reinforced materials. (Bunsell, 1998) Also, during the preparation of carbon-fiber-reinforced materials, a lot excess material is required hence this high volume construction lead to an increase in weight hence increase in fuel usage. Also, the technologies available for the exploitation and preparation of carbon-fiber-reinforced materials is very labour and time intensive hence making them costly. According to Ferrari’s technical director, the use of carbon-fiber-reinforced materials require a lot of material hence this high volume does not realize the potential of the material due to the high content of resin, excess thickness and the fibers are not use to their full potential. (Rapra, 2010) Most manufactures are moving away the use of carbon-fiber-reinforced materials due to a preference on bonding between joins than welding. For instance, friction is applicable for simple flat surfaces and shapes as compared to bonding technique that enables the use of more alloys as compared to welding. Shifting away from the use of carbon-fiber-reinforced materials will help manufacturers use both epoxy liquid and tape as bonding materials. This type of connection provides stronger grip and makes the joint susceptible to some peeling forces. The use of epoxy liquid is important in metal matrix composites since they yield stiffness compatible with most metals. However, with the abandonment of the use carbon-fiber-reinforced materials for metals, there is need to trim weigh and this can be done through the use of matrix composites. (Carney, 2011) Bibliography Bunsell, A. R. 1998. Fibre reinforcements for composite materials. Amsterdam: Elsevier. Carney, D. 2011, November 10. Ferrari prefers aluminum over carbon fiber. Retrieved April 16, 2014, from http://articles.sae.org/10391/ Caspe, R. J., Day, R., Wilkinson, A., & University of Manchester. 2010. Through-thickness melding of advanced carbon fibre reinforced polymers. Manchester: University of Manchester. David, C. 2007. Freedom CAR and Low Cost Carbon Fiber for Automotive Applications. 12 Aeronautical, Mechanical, Chemical and Manufacturing Engineering Conference, 2(7). Hilado, C. J. 1994. Carbon composite and metal composite systems. Westport, Conn: Technomic Pub. Co. Malnati, P. 2013, January 3. Faster cycle, better surface: Out of the autoclave: Composites World. Retrieved April 16, 2014, from http://www.compositesworld.com/articles/faster-cycle-better-surface-out-of-the-autoclave Pimenta, S., & Pinho, S. T. 2011. Recycling carbon fibre reinforced polymers for structural applications: Technology review and market outlook. Waste Management, 3(5). doi:10.1016/j.wasman.2010.09.019 Rapra, S. (2010). Polymers in Defence and Aerospace Applications 2010. Shrewsbury: ISmithers Rapra Pub. Read More