Non-orthogonal FE model with stress smoothing for progressive damage analysis of shear pre-deformed 3D angle-interlock woven composites under compression

Abstract

3D angle interlock woven fabric usually needs to produce pre-deformation to meet the requirements of the complex shape of the target configuration. This cause the internal fabric angle to change, which makes it difficult to predict the mechanical properties and damage evolution. A novel non-orthogonal mesoscale finite element (FE) model considering local stress smoothing is proposed to predict the effective mechanical properties and reveal the damage evolution process of shear pre-deformed 3D angle-interlock woven composites under compressive load. The spurious stresses in the vicinity of the different material interface caused by the stepped block-like voxel boundaries are efficiently eliminated to improve the failure prediction accuracy. The predicted warp directional compressive stress-strain curves are good agreement with that of experiments, and the failure morphologies are verified by Scanning Electron Microscopy (SEM). The validated simulation model is further to investigate the effects of shear angle on the effective compressive stiffness and strength of 3D angle-interlock woven composites in different direction. And the effects of shear pre-deformation and stress smoothing on the damage and failure mechanisms are discussed. This study is great helpful of providing reliable guidance for analyzing and designing the pre-deformed 3D woven composite complex structures, such as aero-engine fan blades.