Foam Cores in RTM Structures, Manufacturing Aid of High-Performance Sandwich?

Abstract

In order to show the potential of foam cores in RTM structures, the German Aerospace Centre DLR has developed several structural demonstrators using an autoclave-based resin injection technology called Single-Line-Injection technology (SLI) in combination with PMI (ROHACELL) foam cores. Some of these demonstrators feature a skin that is tolerant to impact by being modified using a Single-Side-Stitching technology. Furthermore the DLR investigates new LRI (Liquid Resin Infusion)/foam core-based design strategies for CFRP fuselage structures that combine highly integrated designs with simple tooling concepts. In the field of series applications the INVENT company in Braunschweig has successfully introduced the LRI/foam-core strategy for the Nose Landing Gear Doors and other class II parts of the newly developed Fairchild Dornier Do 728 Airliner. Even the Do 728 nose boom adapter, a heavily loaded and extremely complex class I structure is manufactured by INVENT with this technology.