Coupled Effects of In‐Plane Fiber Waviness and Circular Cutout on Axial Buckling Behavior of Glass‐Epoxy Composites

ABSTRACT Coupled effects of in‐plane fiber waviness and the presence of circular cutouts in glass fiber‐reinforced laminates (GFRLs) were investigated under the action of buckling load. The research evaluates the wave severity, structural integrity, and failure processes of composites by combining cutting‐edge image processing methods with experimental testing. Composites were fabricated using a novel manufacturing technique to induce in‐plane fiber waviness. Image processing techniques, using the OpenCV library in Python, were applied to measure the waviness ratio (WR) in the composites. These measurements were validated by comparison with instrumental results to ensure accuracy. Circular cutouts were drilled in the waviness region to investigate the coupled effects of WR and cutouts. These composites were then subjected to actual tests to assess their buckling behavior. The findings of the study reveal that the composite without waviness and without a circular cut exhibited the highest critical buckling load. Further, composites exhibiting a WR of 0.032, 0.042, 0.052, 0.062, and 0.072 showed about 19%, 22%, 24%, 26%, and 28% decrease in load‐bearing capacity, respectively. Moreover, a significant coupled impact was seen when these composites included a circular cutout of 4 mm diameter, which resulted in 25%, 28%, 32%, 35%, and 38% reduction in their load‐bearing capacity, respectively. Additionally, finite element (FE) simulations reliably assess GFRL by capturing buckling behavior with the variation of 3.15%–7.79% with respect to experimental results. Finally, tested composites were examined through a scanning electron microscope (SEM) to explore the modes of failure and to understand their failure mechanism.