Automated RVE computations for evaluation of microdamage initiation in structural stitched non-crimp fabric composites

Abstract

<jats:p> This contribution presents an approach to generate unit-cell models of structural stitched non-crimp fabric composites. Resin-rich regions and out-of-plane undulations caused by the stitching yarn are represented by initially straight discretised lines, while the stitching yarn is represented initially by a single discretised line which can be transformed into a multi-line configuration to model stitch cross-section variations. The discretised lines are shaped by geometrical operations with a contact treatment and boundary conditions being used to account, respectively, for line interactions and to control the shape of the bottom and top surfaces of each lamina respectively. A fiber-reinforced distorted zone with local variations in fiber volume fraction and fiber direction is modelled in cross-sections of the lamina in a post-processing step. Models for different stacking sequences and stitching parameters are then automatically generated and subsequently being in the stiffness calculation and damage initiation assessment using finite element based mechanical simulations. </jats:p>

Mechanical behavior of three‐harness twill woven composite plates under tension loading

“…[27][28][29] Furthermore, some authors have optimized the geometric modeling methods, including but not limited to reducing the amount of input data and calculation cost and solving the problems to establish strongly curved yarn, and alleviating the yarn surface interpenetrate. [30][31][32] Once the geometric model, which is close to the actual structure, was established, an appropriate mesh generation strategy was required to obtain the finite element model and get calculation results. Several researchers [33][34][35] have reconstructed the internal structure of 3D woven composites using conformal meshes and conducted mesoscale mechanical property analysis.…”

“…Based on XCT, some authors put forward modeling methods that can reflect the characteristics of mesostructure at a highly detailed level 27–29 . Furthermore, some authors have optimized the geometric modeling methods, including but not limited to reducing the amount of input data and calculation cost and solving the problems to establish strongly curved yarn, and alleviating the yarn surface interpenetrate 30–32 …”

Shock Waves in 3d Textile Composite Subject to Hypervelocity Impact

“…The unit cell-based modeling method was used for a three-dimensional woven compost unit, in which changes in the cross-sectional shape of the connecting thread in the configuration were considered. To investigate the effect of stitching on the laminating strength of multilayer composites that are affected at low speeds, finite element models based on progressive damage analysis have been used to simulate the mechanism of damage formation [19,20]. As described above, honeycomb composites structures are widely used in space applications due to their lightweight components.…”

Formability Characterization of Stitched Preform Toward Applying for Composite Structures

“…On the other hand, it is recognized that stitching sites serve as stress concentration zones that initiate damage. Some studies have suggested that stitching several layers together and curing using liquid molding technology can reduce manufacturing costs, but stitching will occasionally result in lower plane properties [11,2]. The rupture and displacement of bers caused by needle penetration within textile fabrics, as well as the presence of gaps and voids around the thickness bers of the troughs, can result in this decrease.…”