Process Modeling of Thermoplastic Matrix Composites

Heat transfer is perhaps the most critical parameter in the processing of thermoplastic matrix composites. Temperature distribution affects the quality and microstructure of the final product in that flow, compaction, melting, and crystallization are thermally controlled processes. Using readily available thermal properties of the composites, a model that predicts the temperature profile within a composite laminate during processing was developed. Graphite-reinforced thermoplastic composites of various thicknesses, up to 80 plies, were fabricated and used to validate the analytical thermal profiles. When compared with empirical measurements, the heat transfer model was shown to generate highly accurate temperature distributions within the composites under various processing conditions. When correlated with the dynamic viscosities of the polymer at various temperatures, t-T-V profiles of the composites during processing can then be obtained.