Abstract
Relationships between impregnation mechanisms, consolidation quality and resulting mechanical properties of CF/PEEK thermoplastic composites manufactured from a commingled yarn system have been investigated. A small compression mould was used to apply the different processing conditions (i.e. pressure, holding time and processing temperature). The consolidation quality of finished samples was characterized mainly through microscopic studies of the microstructure of the material associated with density measurements and evaluations of mechanical properties using a small transverse flexure testing facility. A model for qualitatively describing the impregnation and consolidation processes in commingled-yarn-based thermoplastic composites was developed, which predicts variations of void content during consolidation as well as the time, temperature and pressure required to reach full consolidation. Good correlations between predictions and the experimental data indicate the success of the approach. For a desired, minimum level of void content (
X
v
= 0.5%), optimum processing windows for manufacturing of CF/PEEK composite parts from the commingled yarn preform are suggested.