EVALUATION OF AN ADDITIVELY MANUFACTURED TOOLING WITH INTEGRATED FUNCTIONALITY FOR THE PRODUCTION OF CARBON FIBER TEXTILE PREFORMS

摘要

The recent progress in additive manufacturing technologies has led to new freedom in respect to part design. Strongly undercut and inner geometries can be manufactured as an integral structure. In the course of the development of an automated preforming process for small batch freeform CFRP components at the German Aerospace Center in Augsburg, the possibility of additive manufacturing for preform toolings was assessed. A segmented preform tooling made from polyamide 12 enriched with aluminum powder was manufactured in a selective laser sintering (SLS) process. Apart from the formative geometry additional functions were integrated in the design, such as pneumatic fixation of plies, heating, cooling as well as the integration of sensors for the monitoring of process parameters. The results of the automated preforming process are generally favorable. However, inherent disadvantages of additive manufacturing, like thermal warpage, need to be considered in order to determine the suitability of the tooling for the preforming process. Therefore, an analysis of geometric variance and performance of the integrated functions is done. The results are critically examined against the background of the preforming process and used to discuss opportunities and limitations of additively manufactured toolings for the general application in production of preforms.