A model based accelerated RTM process design for optimal performance

Abstract

Typical carbon-fiber reinforced polymer (CFRP) composite high-rate manufacturing processes require a multi-physics understanding of the key material and process design variables. A model-based approach may deliver an optimized manufacturing process and yet require experimental validation of quality and mechanical performance to make it an acceptable solution to the industry. The models, especially if 3D, are complex and require extensive characterization with a cross-functional level of resources. This study captures (A) the development of a 1D multi-physics heuristic model applicable to any material system, and (B) the development of an accelerated resin transfer molding (RTM) process design for low-permeability fiber reinforcement using this 1D heuristic model. The laminates manufactured using this model-based accelerated approach meet the specifications on quality and key mechanical properties. Hexcel's biaxial IM8 HiMax® non-crimp fabric with a thermoplastic veil and 1078-1 resin are chosen for the study to develop a process design methodology for (177 °C) cure epoxy. Multi-physics material models of IM8 HiMax® and 1078-1 resin are used to simulate and predict the optimal cure cycles. Critical mechanical testing compares the outcomes from different cure cycles, including a baseline process nominally followed by the industry. Results show that the accelerated-cure panels (50 % cycle time compared with the baseline) are of good quality and perform just as well regarding the mechanical properties. This model-based approach can be extended to more complex geometry and structures for this material system and/or applied to other composite material systems.