A new simple analytical approach for predicting all possible damage modes of Uni-Directional (UD) hybrid composites and their stress–strain response in tensile loading is proposed. To do so, the required stress level (fragmentation, delamination final failure) are assessed separately. The process UD can then be predicted based on order each mode. Using developed method, a series standard-thickness glass/thin-ply carbon was tested very good pseudo-ductile with 1.0% strain no load drop until...

A comprehensive set of thin-ply pseudo-ductile unidirectional interlayer hybrid composite materials comprising S-glass and a variety thin carbon prepregs was designed characterised. Unique elastic–yielding–hardening type stress–strain responses similar to those ductile metals were achieved through fragmentation stable pull-out the layers, generating range initial moduli, pseudo-yield strains, plateau stresses pseudo strains for various configurations. The typical failure modes composites...

The aim of this research is to manufacture intermingled hybrid composites using aligned discontinuous fibres achieve pseudo-ductility. Hybrid composites, made with different types that provide a balanced suite modulus, strength and ductility, allow avoiding catastrophic failure key limitation composites. Two material combinations high carbon/E-glass modulus were selected. Several highly well dispersed short fibre carbon/glass ratios manufactured tested in tension order investigate the carbon...

Experimental results are presented which allow the hybrid effect to be evaluated accurately for thin ply carbon/epoxy–glass/epoxy interlayer composites. It is shown that there an enhancement in strain at failure of up 20% very plies, but no significant thicker plies. Hybrid specimens with thick carbon plies can therefore used measure reference carbon/epoxy strain. The latter significantly higher than from all-carbon due stress concentrations load introduction. Models illustrate mechanisms...

A new, partially discontinuous architecture is proposed to improve the mechanical performance of pseudo-ductile, unidirectional (UD) interlayer carbon/glass hybrid composites. The concept was successfully demonstrated in different laminates with high strength and modulus carbon S-glass epoxy UD prepregs. novel provided pseudo-ductile tensile stress–strain responses a linear initial part followed by wide plateau second part, all connected smooth transitions. best configuration showed 60%...

A variety of thin-ply pseudo-ductile unidirectional interlayer hybrid composite materials comprising high modulus and strength thin carbon fibre/epoxy prepregs was investigated. The central plies fragmented delaminated stably from the outer layers under uniaxial tensile loading in materials. These pseudo-ductility mechanisms resulted favourable, metal-like stress-strain responses featuring pseudo-yielding, a stress plateau further rise before final failure. initial elastic up to 240 GPa,...

The effect of different parameters on the gradual failure and pseudo-ductility thin UD hybrids is studied using an analytical method developed recently. Damage mode maps are proposed to show geometric for a specific material combination. This type map novel efficient find optimum configuration also indicates importance layers achieve in practice. parametric study reveals that there always trade-off between "yield stress" amount pseudo-ductility; higher yield stresses leads lower vice versa....

This paper investigates the link between acoustic emission (AE) events and corresponding damage modes in thin-ply UD carbon/glass hybrid laminates under tensile loading. A novel configuration was investigated which has not previously been studied by AE, where were fabricated embedding thin carbon plies standard thickness translucent glass to produce progressive fragmentation of layer delamination interface. criterion based on amplitude energy AE event values established identify failure...

Two novel approaches are proposed for elimination of stress concentrations in tensile and compressive testing unidirectional carbon/epoxy composites. An interlayer hybrid specimen type is testing. The presented finite element study indicated that the outer continuous glass/epoxy plies suppress at grips protect central from premature failure, eliminating need end-tabs. test results confirmed benefits specimens by generating consistent gauge-section failures tension. developed four point...

Un-notched and notched tensile response damage accumulation of quasi-isotropic carbon/epoxy hybrid laminates made ultra-high modulus intermediate carbon fibre/epoxy thin-ply prepregs were studied. It was confirmed that the ply fragmentation demonstrated previously in unidirectional hybrids as a successful pseudo-ductility mechanism can be transferred to multi-directional laminates. Furthermore, reduced notch sensitivity specimens for both open holes sharp notches result local around notch.

This study exploits the potential of thin-ply carbon/glass hybrid laminates to generate high performance Quasi-Isotropic (QI) composite plates that show pseudo-ductility in all fibre orientations under tensile loading, overcoming inherent brittleness conventional composites. Two types QI lay-ups with 45° and 60° intervals, i.e. [45/90/-45/0] [60/-60/0], were used fabricate novel architectures a T300-carbon laminate sandwiched between two halves S-glass laminate. The fabricated then loaded...

This paper introduces novel structural health monitoring (SHM) sensors to improve the detection of low energy impact damage in laminated composites. The sensor is a purposely designed thin-ply hybrid composite, composed layer unidirectional S-glass/epoxy and another ultra-high modulus (UHM) carbon/epoxy. was incorporated onto both impacted face back substrate plate made from T800 carbon/MTM49-3 epoxy prepregs with stacking sequence [45/0/90/-45]4S. A series drop tower tests were conducted on...

In this study, acoustic emission (AE) technique is used to investigate different time-to-failure mechanisms of delamination in glass/epoxy composite laminates. Woven and unidirectional layups were subjected the double cantilever beam, end notch flexure, mixed-mode bending tests generated AE signals captured. Discrimination events, caused by types damage mechanisms, was performed using wavelet packet transform (WPT) fuzzy clustering method (FCM) associated with a principal component analysis...

This paper investigates the effect of fibre properties composite structures on mechanical performance and formation low-velocity impact damage. Quasi-static indentation tests were conducted a comprehensive set scaled Quasi Isotropic (QI) S-glass/8552 epoxy QI IM7-carbon/8552 laminates, comparing changes in both in-plane dimensions fully three-dimensionally cases. Due to higher thickness S-glass results normalized by scaling rule have fair comparison between behaviour. The demonstrated that...

Many researchers have used continuum damage mechanics for modelling in standard composites. This approach is intrinsically suitable the progress of modes spread over specimen, which has been widely reported pseudo-ductile hybrid To authors' best knowledge, this paper first numerical model based on proposed The constitutive uses a thermodynamically consistent to compute progression material. Experimental stress-strain curves and failure pattern carbon/glass lay-ups with gradual taken from...

Laser-induced graphene (LIG) enables the creation of cost-effective sensing devices via one-step laser scribing on organic substrates. This work aims to demonstrate feasibility LIG as an embedded damage sensor in structural composite materials. was produced inexpensive cork substrate using a low-power blue light engraving system. The characterised establish relationship between LIG’s physical properties and lasing parameters. Using parameters which offer optimal properties, mesh pattern...

<title>Abstract</title> Achieving robust low-resistance electrical contact with carbon fibres embedded in polymeric matrices is a challenge and different electrode fabrication methods, mostly for after composites are cured have been examined the literature. This paper investigates use of metallic foils co-cured on top surface fibre reinforced polymer (CFRP) to form stable electrodes. Different materials effects their geometry variation CFRP interface resistance (IR) studied experimentally....