A Mechanical Study of a Glass Fabric-Thermoplastic Resin Composite: 3D-DIC and X-ray tomographic observations explained by numerical simulations based on a spectral solver

TL;DR

This study combines 3D-DIC, X-ray tomography, and numerical simulations to analyze the mechanical behavior and damage initiation in a glass fabric-thermoplastic composite at the mesoscale.

Contribution

It introduces a spectral solver-based numerical approach that accurately predicts local stress and strain fields, validated by experimental measurements.

Findings

Good agreement between simulations and 3D-DIC measurements

Identification of stress concentration regions within the microstructure

Confirmation of damage initiation in high-stress subregions

Abstract

In the study presented in this paper, we analyzed the mechanical response of a glass fiber plain weave/polymer composite at the fabric millimetric mesoscale. The detail of the stress and strain fields in a fabric repeating unit cell was numerically calculated using CraFT (Composite response and Fourier Transforms), a code specifically conceived for simulating the mechanical behaviour of materials with complex microstructure. The local strain fields obtained by simulation were found to be in very good agreement with measurements carried out using 3D Digital Image Correlation (3D DIC). From numerical stress fields calculated with the CraFT solver, we also highlighted the subregions inside the periodic mesostructure where there is maximum stress. Furthermore, with X-ray tomography post mortem measurements, we were able to confirm that certain damage modes were well initiated in these microstructure subregions of stress concentration.