Warpage of Flat Composite Part Induced by Liquid Resin Infusion (LRI) Processes

Abstract

Composite materials manufacturing of high performance part require high cure temperature in a multi-material environment. It results multi-scale product-process-resources interactions, which are responsible for low dimensional fidelity between the mould and the part shape. Because of the different implementation by LRI processes, warpage cannot be account only for tool-part interaction like by prepreg-autoclave processes. An interaction between the part and the moulding resources are characterized, which is in majority responsible of the part warpage. Experimental setups were developed to investigate the main mechanisms of deformation present by LRI processes. The deformations due to the part-moulding resources interaction have been experimentally isolated and the influences of main driver parameters have been quantified. A simple mechanical model based on the thermal and cure behaviours of the part and the resources are proposed to predict the warpage. The model correlates with an acceptable accuracy the experimental warpage of different part lengths and part thick.