Abstract
Composite materials have gained the attention of the automotive industry to substantially reduce vehicle weight, reduce CO2 emissions and improve the fuel economy of next generation vehicles. Thermosetting matrix technology combined with glass or carbon fiber reinforcements are well suited for structural applications where mostly steel and aluminum are used today. However, the lack of fast production techniques and fast reacting matrix technologies have limited composites use to low volume production models. A new generation of epoxy resin systems has been developed that allows the rapid processing of structural composites for medium to high volume models. These advanced formulations maintain the excellent properties of traditional epoxy-based composites, yet the tested systems can process in a matter of minutes using modern manufacturing technologies such as the high pressure resin transfer molding (HP-RTM) process. The advanced formulations are unique in that they provide a long enough injection window for a robust impregnation of the reinforcing fibers while still enabling an extremely short cure cycle. The results from this development show that structural composite components can be produced economically and in high volume using today’s innovative resin and process technology. Introduction Automotive manufacturers, particularly the European premium carmakers, are working vigorously on reducing the weight of their fleets and have begun introducing composite materials on higher volume commercial models. Fiber reinforced plastics using either glass or carbon fibers as reinforcement and thermosetting epoxy resin matrices are an extremely powerful material combination for saving weight in structural applications. As equipment manufacturers have continued to make improvements to the range of composite processes such as prepreg, filament winding, compression and resin transfer molding, resin manufacturers have had to develop new resin systems to compliment these high volume / high speed processes. Requirements include shorter cure time, VOC-free and REACH-compliant systems that do not sacrifice the desirable characteristics of traditional epoxy resins. This paper focuses on the development of material technology for the resin transfer molding (RTM) manufacturing process which is among the leading technologies for making structural composite parts. The entire process, as illustrated in Figure 1, requires a short cycle time (< 5 minutes) to be viable for automotive mass production volumes. Today, the main bottlenecks are the manufacture of the preform (Steps 1-2), and the actual injection and cure of the part (Step 4).
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have