Impact Wear Performance Of Fdm-Printed Pla: Influence Of Infill Pattern And Density

This study investigates the influence of infill pattern and infill density on the impact wear behavior of FDM-printed PLA specimens. Samples were manufactured using three internal architectures (cubic, gyroid, and triangular) at two infill densities (75% and 100%) and tested under cyclic impact loading conditions. Crater diameter, crater depth, and wear volume were quantified using three-dimensional optical profilometry.The results indicate that increasing the infill density significantly improved wear resistance by reducing crater dimensions and material loss. Among the investigated architectures, the triangular pattern exhibited the lowest wear volume (0.044 mm³) and the most stable crater morphology, indicating a more efficient load-transfer capability. Statistical analysis indicated that crater diameter was significantly affected by infill pattern and, in the two-way model, by infill density, whereas crater depth and wear volume showed non-significant but consistent trends.Contact mechanics analysis indicated that the calculated Hertzian contact pressures exceeded the yielding threshold of PLA, demonstrating that the wear process occurred in an elastic–plastic regime. Cross-sectional optical observations further revealed that damage evolution transitions from subsurface collapse in cubic structures to surface-confined deformation in triangular patterns. These findings highlight the critical role of internal architecture in determining the impact wear performance of additively manufactured polymer components.