On the strain-rate dependent compressive failure behavior of 2.5D woven composites

Understanding the mechanical failure behavior of 2.5D woven composites (2.5DWC) is challenging due to their complex fabric configurations and multi-scale structural properties. This challenge is particularly prominent in the realm of dynamic mechanical properties and damage failure mechanisms under high strain rates. Therefore, a comprehensive approach combining a series of quasi-static and dynamic mechanical tests with mesoscale finite element simulation methods is adopted to perform an in-depth analysis of the mechanical response and progressive damage behaviors of a Twilled 2.5D Woven Composite (T-2.5DWC) under different strain rate loads. The results indicate that the compressive strengths as well as the failure behaviors of the T-2.5DWC exhibit an obvious strain rate strengthening effect in both the weft and warp directions. In addition, the rate-dependent finite element model developed in this study accurately simulates the compressive modulus and strength of T-2.5DWC along both the warp and weft directions under various strain rates.