Supplementary Material for “Effects of processing parameters on the Mode I interlaminar fracture toughness of additively manufactured continuous glass fiber reinforced PEEK composites”

The study employed Response Surface Methodology (Box–Behnken design) to systematically investigate the effects of three key processing parameters—nozzle temperature (400–440°C), printing speed (1–5 mm/s), and layer thickness (0.16–0.24 mm)—on GIC.

Core data include load-displacement curves and calculated GIC values from Double Cantilever Beam (DCB) tests, crystallinity measurements obtained via Differential Scanning Calorimetry (DSC), and microstructural images and surface roughness data acquired through optical and laser confocal microscopy. Additionally, the dataset provides input parameters and predictive results from an interlayer fusion model based on thermal history, molecular diffusion, and interfacial contact mechanisms, which demonstrated high consistency with experimental results (coefficient of determination R² ≈ 0.972).