Title: Effect of Layup Architecture and Notch Formation on the Fracture Toughness of 3D-Printed Glass Fiber-Reinforced Nylon Composites

Authors: Jacey Wright, Morgan Sikes, Peter Sheldon, Siavash Sattar

DOI:

Abstract: As 3D-printed continuous and short fiber-reinforced composites find increasing use in structural and load-bearing applications, understanding their fracture behavior is essential for reliable design. This study investigates the fracture toughness of glass-fiber-reinforced nylon composites fabricated via fused filament fabrication (FFF), with a focus on the effects of raster orientation and crack-initiation method on damage evolution. Specimens were produced with multiple layup architectures, 0°, 90°, 45°, and concentric, and tested under Single Edge Notch Bending (SENB). Pre-crack geometries were introduced either through direct printing or post-processing via precision cutting and razor-tap sharpening, enabling comparison between manufacturinginformed and idealized notch formation. Full-field strain evolution was captured using in-situ Digital Image Correlation (DIC), enabling detailed visualization of crack initiation, propagation, and process-zone development. The results demonstrate strong dependence of fracture toughness on fiber orientation and notch-generation method, with printed-notched samples exhibiting larger process zones and more progressive crack growth compared to razor-sharpened notches. These findings provide insight into raster-dependent fracture mechanisms in FFF-fabricated fiber composites and inform the development of more accurate manufacturing-aware failure models for 3D-printed structures.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 124

Pages: 12

Price: $24.00