Manufacturing Process for Automated Preforming of Complex, Double-Curved Components Based on the Diaphragm Method

Abstract

At the German Aerospace Center (DLR), Center for Lightweight Production Technology (ZLP) Augsburg automation solutions for manufacturing processes of extensive fiber composite components are developed. One challenge in this context is the automated preforming process of complex, double-curved geometries. Here, dry fiber cut pieces are transferred from a flat to a three-dimensional state. In order to fix the single layers of the stacking, the fiber package is being compacted and the powder binder system is activated using thermal energy. In addition, double-curved component geometries inhere particularly high requirements on the preforming process, since the fiber materials must not only be deformed, but also be draped. With the state of the art, the production of double-curved components can only be carried out manually, due to the high process complexity. Therefore scientists at the ZLP Augsburg developed an integrated preform manufacturing process, beginning at single cut piece handling till supply of the finished preform. Focus was set on a diaphragm based preforming mechanism that can be directly controlled regarding its forming behavior on the preform to ensure an adequate preforming of the carbon fiber semi-finished product. This paper focuses the challenges of automated production processes for complex, double-curved component geometries and presents one automation solution developed at ZLP Augsburg.