Prediction of warping in thermoplastic AFP-manufactured laminates through simulation and experimentation

Abstract

The thermoplastic automated fiber placement (T-AFP) process is a non-autoclave method for in situ consolidation of thermoplastic composite material on a piecewise constructed laminate. High thermal gradients and nonlinear material behavior, especially due to crystallization, make predictions of process-induced stress and warping difficult. This article describes a method for simulating parts manufactured by T-AFP using a detailed material model to capture the dynamic nature of the process. The material model is flexible and can be altered to describe different semi-crystalline matrices, in this study focusing on low-melt polyaryletherketone. Two laminate panels are simulated within this work and assess the impact of a heated tooling on overall part warping. Panel warping is validated by performing 3D-scans of T-AFP-manufactured laminates produced using the same parameters as the simulation. The results show a good match between numeric and experimental warping, especially for heated tools, thus, providing a useful method for predicting laminate warping and reducing the demand on manufacturing experimentation.