Characterisation of mechanical behaviour and damage analysis of 2D woven composites under bending

Abstract

Additional Information:• NOTICE: this is the author's version of a work that was accepted for publication in Composites Part B: Engineering. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document.Changes In this paper, flexural loading of woven carbon fabric-reinforced polymer laminates is studied using a combination of experimental material characterisation, microscopic damage analysis and numerical simulations. Mechanical behaviour of these materials was quantified by carrying out tensile and largedeflection bending tests. A substantial difference was found between the materials' tensile and flexural properties due to a size effect and stress stiffening of thin laminates. A digital image-correlation technique capable of full-field strain-measurement was used to determine in-plane shear properties of the studied materials. Optical microscopy and micro-computed tomography were employed to investigate deformation and damage mechanisms in the specimens fractured in bending. Various damage modes such as matrix cracking, delaminations, tow debonding and fibre fracture were observed in these microstructural studies. A two-dimensional finite-element (FE) model was developed to analyse the onset and propagation of inter-ply delamination and intra-ply fabric fracture as well as their coupling in the fractured specimen. The developed FE model provided a correct prediction of the material's flexural response and successfully simulated the sequence and interaction of damage modes observed experimentally.

Dynamic bending behaviour of woven composites for sports products: Experiments and damage analysis

“…Due to this minor difference, the number of tows in the warp and weft specimens along their longitudinal plane was 13 and 12.85, respectively, based on 25 mm width of the specimens tested. Detailed parameters of the twill woven CFRP composites are given in the authors' work [15,17].…”

The effect of off-axis angles on the mesoscale deformation response and failure behavior of an orthotropic textile carbon-epoxy composite

“…As the loading process progresses, the matrix starts dominating the mechanical behavior. Once the local shear stress in the matrix exceeds the shear strength, plastic flow occurs and the fiber bundles partially undergo stretching and realigning towards the loading direction (fiber trellising phenomenon [4,25]), consequently exhibiting the large non-linear deformation response at macroscopic scales.…”

Effects of Weave Styles and Crimp Gradients on Damage Tolerance and Energy-Absorption Capacities of Woven Kevlar/Epoxy Composites

“…Ullah et al 4 performed quasi-static on-and off-fiber axis tension and three-point flexure tests of twill (2x2)-woven carbon laminates reinforced with a TPU matrix. Ullah et al 4 used digital image correlation (DIG) to measure the in-plane shear properties using ±45° off-axis tension tests. The on-fiber axis tensile tests exhibited quasi-brittle fracture behaviors; the off-fiber axis tensile behavior was significantly nonlinear at the low and high stress levels.…”