Paintable for the series"Series-ready lightweight construction solutions, visually and haptically appealing surfaces as well as function and process integration are increasingly in demand above all in the automotive and transportation sectors. With the roof module for the Roding Roadster of Roding Automotive GmbH presented at the K 2013 trade show, we have demonstrated the efficient series production of premium quality components for the automotive industry. It gives us all the more joy that it has now won us the Materialica Award in the category of 'Surface and Technology'," explains Erich Fries, Head of the Composites/Surfaces BU at KraussMaffei.
The component is produced using the Surface-RTM process (surface resin transfer molding) developed by KraussMaffei in collaboration with partners. Paintable components are created by flow-coating the Surface-RTM component surface with a polyurethane layer directly in the cavity. This eliminates the need for any additional intermediate steps such as adding a primer or pre-finish. That saves on time-consuming rework, which can amount to up to 60 percent of the costs per component. The metering systems and the mixing heads operate in the high-pressure range during the surface resin transfer molding process. This makes it possible to use fast-reacting matrix resins. This shortens the cycle times to under 6 minutes, so that large quantities can be produced with the surface resin transfer molding process. The high fiber content of 50 percent by volume in the substrate ensures excellent mechanical properties with low component weight.
The award-winning roof module consists of a CFRP continuous fiber in a quasi-isotropic configuration and has a surface area of approximately 0.45 m2. The part is 2 mm thick and its surface material is around 0.2 mm thick. It has a fiber content of around 50 percent. The C-RTM (compression) process also allows for optimum fiber wetting and low fiber displacement. In addition to the two partners who supplied PU systems, Henkel and Rühl Puromer, there are several other companies in KraussMaffei's network of expertise. Dieffenbacher, Zoltek, Chomarat, Alpex, Mühlmeier and Roding Automotive were part of the joint trade-show project and involved in its implementation.