In respect of weight reduction an increasing request for light weight materials exists in the automotive industry. The compression molding of sheet molding compounds (SMC) has been established as a cost-efficient and widely applied process for semi-structural automotive components, especially in commercial vehicles. The deficiency of this material is the relatively low Young's modulus, which prevents these materials from being used in loaded structures. Therefore the idea was to increase the performance of these materials by forming a sandwich, but in principle use the same fast and cost-effective process of conventional SMC. The principle of this new technology is based on a one-step process using one sheet containing a blowing agent disposed between two conventional SMC sheets in the mold. By closing the mold the three layers are compressed and heated up until the expansion of the core material starts. The foaming process resulting from the expansion of the core material is controlled by a defined opening motion of the mold according to the requested sandwich height. After the foaming process the curing of the part is completed. The result is a rigid lightweight sandwich structure. The advantages of the One Step Sandwich-SMC in comparison to typical sandwiches are the decrease in production cost and the recycling properties, since no separation of the single layers is required (single material system) and since additionally the core layer may contain a high amount of SMC scrap material. The developing process of this technology was conducted by the simultaneous integration of fundamental research (material development, testing, processing technology) and by the development of the structural part (part conception/design). This demonstrator component is the front hood of a commercial vehicle, the Mercedes-Benz Actros, which was produced with optimized processing parameters. For the demonstrator chosen a cost potential of 30 % and a weight reduction potential of 10 to 15 % were determined.
One-step-sandwich-SMC
2001
6 Seiten, 11 Bilder, 1 Quelle
Aufsatz (Konferenz)
Englisch
IuD Bahn | 1999
|One Step Sandwich SMC - Verfahren zur Herstellung von leichten Fahrzeugteilen
Kraftfahrwesen | 1999
|Sandwich Panels Produced from Sandwich-Fabric Preforms
British Library Conference Proceedings | 1994
|SANDWICH PANEL AND METHOD FOR MANUFACTURING SANDWICH PANEL
Europäisches Patentamt | 2015
|