Mechanical Properties Prediction of 2.5D Woven Composites via Voxel-mesh Full-cell Model

Considering the difficulty of generating high quality meshes for the representative volume cell (RVC) of 2.5D woven composites (2.5DWC), a voxel-mesh full-cell model is developed in this paper. Herein, microscopic characterizations of 2.5DWC are performed, and the geometric relationship of the microstructure are established. For comparative analysis, six models are built, including a consistent-mesh full-cell model (CFM), three voxel-mesh full-cell models (VFM) with different mesh sizes, and a consistent-mesh unit-cell model (CUM) and its corresponding voxel-mesh unit-cell model (VUM). Based on these six models, the stiffness and strength of 2.5DWC are predicted, and the predicted values are compared with experimental results. The comparison results show that the VFM can predict mechanical properties and damage behavior of 2.5DWC more accurately when the mesh size is fine enough to reflect the microstructure of the material. Furthermore, a parametric analysis is carried out employing the VFM to evaluate the influence of the woven parameters on the mechanical properties of 2.5DWC. It is found that as the warp arranged density increases and the weft arranged density decreases, the mechanical properties in warp and weft directions increase and decrease, respectively. This work provides a more accurate and practical model for the mechanical properties of 2.5DWC predicted in engineering, which is of great engineering significance.