Investigation on the compressive damage mechanisms of 3D woven composites considering stochastic fiber initial misalignment

This paper investigates the compressive damage mechanisms of 3D woven composites through a coupled numerical-experimental approach. A comprehensive progressive damage model, capable of characterizing the fiber kinking failure, transverse inter-fiber crack, matrix damage and interfacial debonding, is developed to capture the damage accumulations by incorporating a novel fracture angle-dependent stress reduction scheme, and the numerical implementation is accomplished accordingly. According to microscopic observations, a periodic representative volume cell with sufficient fidelity, including fiber yarns, matrix pockets and yarns/matrix interface, is extracted from the whole interlaced architecture. Moreover, the influence of inhomogeneous fiber initial misalignments on the compressive performances is parametrically investigated by adopting three stochastic distributions, which are implemented through a compiled user-defined subroutine. To validate the reliability of the proposed progressive damage model, some corresponding experiments of 3D woven composites are conducted. The numerically predicted strengths and damage development of constituents exhibit good consistency with the available experimental results.

Automated summary

This paper investigates the compressive damage mechanisms of 3D woven composites through a coupled numerical-experimental approach, and develops a comprehensive progressive damage model capable of characterizing damage accumulations. The influence of inhomogeneous fiber initial misalignments on compressive performances is parametrically investigated, and the proposed model is validated through corresponding experiments.