Abstract
Due to their high potential in lightweight designs composite sandwich structures with foam cores are gaining in importance in the automotive industry. To carry localized loads, sandwich structures require load introduction elements. In current solutions applied in the aerospace industry the inserts are embedded after the sandwich panels have been manufactured. This is very time consuming and therefore too expensive for automotive industry. In this paper, two new approaches are investigated experimentally, where the inserts get integrated during the preforming process or during the foam core manufacturing. With these manufacturing methods the performance and failure behavior of various insert geometries and different foam core densities will be determined by static pull out tests.
1. Introduction
Increasing demands for lower CO2 emissions and fuel consumption in the automotive industry require new lightweight structures. Therefore designs from the aerospace sector are gaining importance for high volume productions of automotive components. Fiber-reinforced plastics (frp) offer great stiffness and strength to weight ratios thus have an outstanding potential for lightweight design. Used in sandwich structures with light core materials and facesheets made of frp, these characteristics can be applied even more effectively. By adding only little weight due to the additional core the structure becomes a lot more rigid for bending, thus less material is needed and lighter parts can be designed. Common core materials are honeycomb structures or polymeric foams. Honeycomb cores are already widely spread in the aerospace industry due to their high specific mechanical properties. They can outperform foam cores in terms of stiffness to weight ratios [1, 2]. However this advantage is balanced out by higher costs [3], making foam cores more suitable for applications in the automotive industry. A further advantage of foam cores is that complex 3D core geometries can be easily manufactured by filling an appendant tool with foam. They also provide good insulation characteristics [4], and show great energy absorption capabilities [5].
