Effect of the Fibre Orientation Distribution on the Mechanical and Preforming Behaviour of Nonwoven Preform Made of Recycled Carbon Fibres

Abstract

Recycling carbon-fibre-reinforced plastic (CFRP) and recovering high-cost carbon fibre (CF) is a preoccupation of scientific and industrial committees due to the environmental and economic concerns. A commercialised nonwoven mat, made of recycled carbon fibre and manufactured using carding and needle-punching technology, can promote second-life opportunities for carbon fibre. This paper aims to evaluate the mechanical and preforming behaviour of this nonwoven material. We focus on the influence that the fibre orientation distribution in the nonwoven material has on its mechanical and preforming behaviour at the preform scale, as well as the tensile properties at composite scale. The anisotropy index induced by fibre orientation is evaluated by analysing SEM micrographs using the fast Fourier transform (FFT) method. Then, the anisotropy in the tensile, bending, and preforming behaviour of the preform is inspected, as well as in the tensile behaviour of the composite. Additionally, we evaluate the impact of the stacking order of multi-layers of the nonwoven material, associated with its preferred fibre orientation (nonwoven anisotropy), on its compaction behaviour. The nonwoven anisotropy, in terms of fibre orientation, induces a strong effect on the preform mechanical and preforming behaviour, as well as the tensile behaviour of the composite. The tensile behaviour of the nonwoven material is governed by the inter-fibre cohesion, which depends on the fibre orientation. The low inter-fibre cohesion, which characterises this nonwoven material, leads to poor resistance to tearing. This type of defect rapidly occurs during preforming, even at too-low membrane tension. Otherwise, the increase in nonwoven layer numbers leads to a decrease in the impact of the nonwoven anisotropy behaviour under compaction load.

Plain-Woven Areca Sheath Fiber-Reinforced Epoxy Composites: The Influence of the Fiber Fraction on Physical and Mechanical Features and Responses of the Tribo System and Machine Learning Modeling

“…6−8 Complementary to the studies reported by various authors, the woven composites have exhibited explicit mechanical behaviors in orthogonal directions under various tests compared to the particle, short, or long fiber composites. 9,10 According to a review article by Ivars et al, 11 the most efficient and cost-effective method for producing composites is to use short, untreated fibers. On the other hand, it has been exposed by many researchers 12−14 that the stress transformation between long fibers (woven) and the matrix is superior to that of short and random-oriented fiber composites.…”

“…According to a review article by Ivars et al, the most efficient and cost-effective method for producing composites is to use short, untreated fibers. On the other hand, it has been exposed by many researchers − that the stress transformation between long fibers (woven) and the matrix is superior to that of short and random-oriented fiber composites.…”

A statistical approach for failure analysis involving uncertainty in determining ply orientation

“…The uncertainty in ply orientation measurement has a significant impact on the predicted laminate strength and stiffness predictions. The literature includes studies of structural and probabilistic failure analysis using the uncertainty of the manufactured composite (see e.g., reference 9,13). Sriramula et al 14 suggested that when investigating local damage and failure characteristics that stochastic computational mechanics may need to be based on random variables.…”

“…Hsu et al 8 used the 2D fast Fourier transformation (FFT) to determine ply orientation of a 16‐ply unidirectional laminate consisting exclusively of plies. Ivars et al 9 also proposed a FFT approach on neat (no resin) fiber systems from SEM imaging to determine the ply orientation to determine the mechanical behavior. Smith and Nelson 10 successfully used the 2D FFT from captured ultrasound waveforms received from testing a unidirectional laminate consisting exclusively of 0, and plies.…”

Advanced Hybrid Joining for Needle-punched rCF Composite-Metal Structures via Compression Moulding Process

“…For instance, Kumar et al [8] studied static shear behaviour of rCF/epoxy nonwovens by identifying interlaminar failure as a critical factor for shear strength. Ivars et al [9] revealed effects of the fiber orientation distribution on the anisotropic mechanical properties of needle-punched rCF nonwovens. Barnett et al [10] showed that rCF/PPS nonwovens offered stable energy absorption under crashworthiness loading.…”