A combined experimental – numerical approach for predicting young’s modulus in additively manufactured thin strut-based structures

Abstract Strut-based structures, such as lattices, produced using additive manufacturing (AM) offer significant potential for applications requiring lightweighting and structural compliance. However, conventional Design for AM (DfAM) approaches often assume idealised material behaviour, which can be misleading for thin strut-based structures where geometric parameters and process-induced effects significantly influence mechanical properties, especially near manufacturability limits. Although prior studies have examined geometric effects, no predictive model has explicitly captured on a strut level how Young’s modulus ( E ) varies as a function of both strut diameter ( d ) and orientation ( θ ). This study employs a combined experimental-numerical approach to more accurately predict mechanical properties. A parameterised test artefact was developed to allow for independently varying both d (0.8–1.6 mm) and θ (30°– 60°), and test samples were fabricated in polyamide using selective laser sintering. These samples were tested in compression to record force-displacement responses and finite element simulations were used to calibrate E for each sample. The results showed that calibrated E values deviated up to 46% from the nominal material modulus, with θ having a stronger effect than d . By isolating the effects of d and θ from higher-order topology (e.g., relative density and nodal connectivity), the results are generalisable across a range of potential structural configurations. A linear polynomial response surface (coefficient of determination, R² = 0.96) was developed to predict E as function of d and θ . Integrating geometry-based calibration, these findings augment DfAM, enabling more accurate, simulation-driven predictions for thin strut-based AM structures.