Thermal performance evaluation of different 3D printed susceptor patterns for use in composite induction welding

Carbon fibre steering offers a pathway to designing composite susceptors that could replace metallic inserts in the induction welding of carbon fibre–reinforced polymer laminates. By tailoring the fibre architecture, the composite itself can act as an integrated susceptor capable of controlled electromagnetic heating. A finite element model is developed in COMSOL Multiphysics to predict temperature evolution and current concentration within such tailored laminates. The model is first validated using unidirectional samples with fibre orientations of 0°, 90°, +45°, and −45°, and subsequently extended to complex susceptor configurations, including circular, concentric, and quasi-isotropic designs. The simulation explicitly accounts for local mesostructural effects to capture anisotropic conduction and edge effects governing heat distribution. Results indicate that the concentric configuration achieves the highest peak temperatures with strongly localised heating; the circular pattern yields radially symmetric temperature fields, and the quasi-isotropic layup provides uniform but less intense heating. Experimental infrared thermography confirms these trends, showing good agreement with model predictions. The work demonstrates that susceptor geometry can be engineered through fibre steering to control induction heating behavior, providing a lightweight, corrosion-free, and sustainable alternative to metallic inserts for joining and repair of thermoplastic composites in aerospace and automotive applications.