Finite Element Analysis of Mathematically Generated Model of Rib 1 × 1 Weft‐Knitted Fabric Under Uniaxial Tension

ABSTRACT Different fiber‐reinforcement structures in composites cause varied mechanical responses by affecting how stress is distributed throughout the sample under various loading conditions. Dry weft‐knitted fabric, characterized by its high stretch rate, exhibits different behaviors when used as a standalone fabric compared to when it is used as reinforcement in composites. The high‐rate elongation property of weft‐knitted fabric arises from the yarns' interaction and the loops' geometry within the fabric, not from the material used. This study examines the tensile behavior of dry weft‐knitted fabrics, intended to serve as reinforcement structures in composite materials. To analyze the impact of this structure, a mathematical model representing the 3D geometry of a Rib 1 × 1 weft‐knitted fabric was developed. The fabric geometry was modeled using Python scripting of the mathematical equations within the ABAQUS FE software for analyzing the modeled geometries. An experimental tensile test was conducted on a commercial Rib 1 × 1 weft‐knitted fabric in both the longitudinal and transverse directions. The fabric exhibited average elongations at break of 262% and 71%, and average maximum tensile forces of 132.8 and 395.6 N in the transverse and longitudinal directions, respectively. Remarkably, the mechanical response and deformation patterns of the numerical and experimental samples closely matched in these tests. Using mathematical models to recreate the complex geometries of these reinforcements in the dry fabric facilitated the accurate prediction of their mechanical responses using numerical analysis. These models are ideally suited for efficiently generating data to train machine learning and artificial intelligence models in the future.