Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Diaphragm forming machine for the automated manufacturing of advanced thermoplastic composite parts

It is well known that thermoplastic composites offer several advantages over the standard thermoset systems, as for example the improved hot wet behaviour, the increased damage tolerance or the recycling possibility. Moreover the most attractive property of thermoplastic composites remains the possible reduction of manufacturing time due to the absence of chemical reaction during the laminate processing. On the one hand this effect was mainly exploited for press forming of simple shaped components, leading only to a few series applications up to now.

On the other hand, it has already been demonstrated that the diaphragm forming process is very suitable for manufacturing complex curvature parts with high laminate quality. However, forming in hot autoclaves is economically insufficient and leads to an increase in overall manufacturing time, which are not acceptable for series productions.

Consequently, a new automated diaphragm forming machine has been developed in order to reduce the manufacturing time and costs. The main part of this machine consists of a pressure vessel (diameter 1000 mm) with integrated infrared heating units. The loading of the diaphragms and the thermoplastic lay up into the forming unit, as well as the removing of the formed part, is done automatically using a handling system. Fully computer controlled process parameters allow parts with reproducible quality to be formed. The integration of infrared heating, combined with a tooling concept based on lightweight tools with reduced thermal mass, has led to a drastic reduction of the manufacturing time. The actual configuration of the diaphragm forming machine permits the manufacturing of high quality, complex shaped APC-2 components (maximum dimensions up to 800 x 800 x 400 mm) in less than 20 min.

Reported by

Swiss Federal Institute of Technology
ETH-Zuerich Bauweisenlabor Wagistrasse 13
8952 Schlieren
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