Defect Prediction During Forming and Consolidation of Composite Materials Using Finite Element Analysis

Forming of composite laminates is an effective manufacturing method that improves repeatability, enables tailoring of material orientations, and reduces time and cost when compared to more labour-intensive alternatives. However, this process is often prone to defects - leading to delays and ultimately scrapping of expensive parts - that are traditionally mitigated through resource intensive trial and error approaches. The risks of the forming process can be mitigated by using process simulation as a tool to develop a robust process window. In order to successfully model the forming of composite materials, the relevant deformation mechanisms and material attributes, shown in Figure 1, need to be considered. This paper presents a finite element simulation framework to predict the occurrence of defects in the forming and consolidation steps of the manufacturing process of fibre reinforced composites. The modelling approach presents a novel discretization strategy for each ply with a superposition of solid and shell elements. This solution uses a coupled pressure-displacement implicit analysis procedure that allows for the simulation of resin flow and is well suited to simulate autoclave consolidation and simple forming cases where through-thickness deformations are important. Simulation results show good agreement with experimental forming trials and other work found in literature in terms of deformation mechanisms and defects observed.