Influence of Process Parameters in Infrared Radiation <scp>AFP</scp> In Situ Consolidation on the Mechanical Properties of Thermoplastic Composites

ABSTRACT Automated fiber placement (AFP) of thermoplastic composites is widely used in aerospace, yet insufficient interlaminar bonding is widespread, and interlaminar shear strength (ILSS) serves as the key indicator of interfacial bonding quality. To address this challenge, a double‐sided infrared (DSIR) irradiation in situ consolidation process is proposed and implemented. A systematic investigation of process parameters and their interactions on CF/PA6 ILSS was conducted, and the ILSS reached 80% of the compression molding benchmark. Short‐beam shear (SBS) tests were performed to characterize the relation between load–displacement, the evolution of ILSS, and the mechanisms by which porosity and crystallinity affect performance. On this basis, an ILSS prediction model was developed, and Shapley Additive Explanations (SHAP) was applied for model interpretability. The results indicate that layup speed showed the most pronounced effect on ILSS, followed by temperature and consolidation force; porosity is significantly negatively correlated with ILSS, whereas crystallinity shows no significant correlation with ILSS. Validation through SBS tests provided strong evidence of the model accuracy, with predictions agreeing well with experimental measurements and a prediction error of only 4%. This study provides an effective approach for AFP process optimization and for enhancing the interlaminar performance of composites.