Adherend surface treatment prior to bonding is pivotal for efficient assembly or repair of carbon fiber reinforced polymer (CFRP) composites. The effect of CFRP surface treatment has gathered much attention in the literature but reported test results on fatigue performance are less prevalent. The effect of surface treatment was extended in this work to cover the static and also fatigue strength of

A polypropylene (PP) homopolymer was reinforced with carbon fiber, glass fiber and wood flour in order to compare their advantages and drawbacks. Interfacial adhesion does not influence stiffness, but it affects strongly properties, i.e. tensile strength and impact resistance. Several local deformation and failure processes take place simultaneously or consecutively in the composites during deformation

As the use of carbon fibre reinforced polymers (CFRP) is continuing to increase in engineering applications, more functionalities will be required. Having an enhanced through-thickness electrical conductivity can be a useful functionality for CFRPs which will minimise their damage from lightning strikes, and will help in their real-time monitoring. For most modification methods there is an adverse

The present study focuses on the experimental and analytical analysis of the deformability behaviour of the triaxial braided fabrics during forming. The mechanical model of the yarns based on the parameters of the reinforcements and the forming process was discussed. On the other hand, the geometric model related to the braiding angle was proposed to describe the yarns and the reinforcement deformations

Delamination is a very frequent damage mechanism that affects the integrity of laminated composites. In this study, the effect of ply orientation on crack growth resistance was analyzed for three different anti-symmetric interfaces (±30°,±45° and ±60°) and compared to a unidirectional baseline under remote mode II loading. Fracture toughness at initiation was the same regardless of the ply orientation

Highly porous, bendable laterally compressed graphene foam (cGF)/acrylonitrile butadiene styrene (ABS) composites are developed by dip coating of ABS on dense cellular-structured, freestanding cGFs. Electrical conductivities of the cGF/ABS composites are enhanced to 6.5 S/cm, higher than that of GF/ABS composites. An electromagnetic interference shielding effectiveness (SE) of 42.4 dB and a specific

Defects such as fiber waviness can occur during the production of thermoplastic composite parts. It is desirable to prevent or minimize fiber waviness as it causes a knockdown in the part’s mechanical properties. However, the mechanisms governing the formation of fiber waviness are currently not fully understood. A setup for the real-time observation of waviness formation during flat laminate consolidation

Ice-templated assembly strategy is an effective method to construct filler networks. The filler networks can be used to increase the thermal conductivity of polymer composites. Herein, silicon carbide nanowires, reduced graphene oxide and cellulose nanofiber were used as assembly units to construct vertically aligned filler networks by ice-templated assembly strategy. Polydimethylsiloxane grafted with

In this paper, the method to unify the definition of woven architectures in textile composites over a wide range of variations has been established. This was achieved via parametrisation of the weaves, which was conducted employing a limited set of clearly defined parameters. Detailed description of these parameters has been given, based of which a wide range of 2D and 3D weaves can be reproduced.

This paper presents a comprehensive characterisation of wood flour geometry for polylactic acid (PLA) wood plastic composites (bioWPCs), and hence explores how the wood flour may influence the microstructure and performance of bioWPCs. The results show that current characterisation of wood flour from the literature can be misleading as they mostly rely on sieve analysis. Image analysis was used to

The use of multi materials within a single composite structure provides many advantages, including component cost reduction, the ability to manufacture complex designs and greater potential for part recyclability. However, these multi materials can often have very different properties and surface chemistries, and can be challenging to join when using adhesives. This research explores a new processing

The in-plane shear behaviour of an uncured composite material (i.e. prepreg sheet, dry fibre preforms etc) is one of the key parameters that influences wrinkles generation in advanced composites manufacturing processes such as automated fibre placement (AFP) and thermoforming. However, there is no standardised test method for the characterisation of uncured unidirectional prepreg subjected to pure

A new treatment condition involving superheated steam (SHS) was proposed to achieve optimal carbon fiber recovery with a minimal decrease in fiber strength. Unidirectional carbon fiber reinforced sheets were exposed to SHS at 650 °C for 1 h with the addition of N2 or CO2 as process gas. The recovery was assessed based on mass change and using thermogravimetry and differential scanning calorimetry.

The magnetic ZnFe2O4 nanoparticles were synthesized and combined with carbon nanotubes (CNTs) to form a unique tangled structure (ZnFe2O4@CNT), and then used as wave absorbing functional nanofillers of polyvinylidene fluoride (PVDF) matrix. The effects of ZnFe2O4@CNT functional nanofillers on the microstructure, crystallization behavior and electromagnetic wave absorption properties of PVDF were studied

SiC/SiC composites reinforced with 3rd generation SiC fibers (Hi-Nicalon S and Tyranno SA3 fibers) are promising candidates for thermomechanical applications in high technology industries. Both composites exhibited a pseudo-ductile mechanical behavior but the HNS/PyC/SiC composite reaches higher failure strains than TSA3/PyC/SiC ones. The mechanical behavior of SiC/SiC composites is linked to the way

The effects of laminate lay-up and multiaxial loading on the failure of multidirectional laminates can be significant. Thus, ply thickness and fibre orientation effects in quasi-isotropic carbon/epoxy laminates subjected to combined tension-shear and compression-shear loading are investigated. Three laminate lay-ups with equivalent thickness and homogenised elastic properties, but with different ply

Through-thickness thickness reductions in laminated composites are essential for weight and aerodynamic efficiency, but they can also be the site of damage initiation. Tensile failure mechanisms of modestly tapered laminates, loaded via gripping their thick and thin ends, and a severely tapered laminate, loaded by contact at its tapered section, were investigated via experiments and high-fidelity finite

Traditional metal foams, which are incapable to meet the heat dissipation demands of today’s electronics industry, were recently reformulated by the incorporation of thermal inclusions of graphite flakes that enhance their heat dissipation efficiency. In this work we manufacture, by means of a one-pot liquid metal infiltration synthesis, new layer-structured multicomponent materials that consist of

By directly curing continuous fiber reinforced thermosets locally onto metal parts, the mechanical performance of these components can be increased significantly by just adding a minimum of weight. Due to the thermal and chemical behavior of the composite material, residual stresses occur and lead to warpage of the structure or failure of the part. This paper deals with a hot-melt, snap-cure matrix

A meso-scale finite element modelling strategy was developed to investigate the effect of hybridisation on the compaction response of multilayer stacks combining glass and carbon dry woven fabrics. It is expected that the electrochemical-mechanical properties of emerging multifunctional hybrid composites are strongly dictated by the morphology of the compacted reinforcements, yet no investigations

The hybrid of graphene oxide nanosheets (GO)-perfluoropolyether (PFPE) was prepared, and polyoxymethylene (POM)/GO-PFPE nano-composite with ultra-low friction coefficient was fabricated via convenient melt processing. POM/PFPE molecules intercalated into GO layers by forming hydrogen bonding with high intercalation ratio and layer thickness, while GO was embedded and homogeneously distributed in matrix

Since the demand for high performance products is ever growing, to combine the characteristics of biomaterials and synthetic polymers through a facile method may stand out as a forerunner to the materials design and application. Herein, waterborne polyurethane/collagen (WPU/CO) composites were prepared by a green facile method. Interactions between collagen and polyurethane segments lead to hybrid

Transparent wood (TW) based on delignified birch veneer and thermoplastic poly(methyl methacrylate) (PMMA) is investigated by uniaxial tensile tests and full-field strain analyses based on digital image correlation techniques. TW is considered as a composite of unidirectional fibers (wood veneer) in a matrix (PMMA). Four in-plane elastic constants along the material axes are reported to enable the

Dual-curable formulation was used to prepare epoxy prepregs with tailored tack and drape. The obtained formulation had enhanced stability during the storage which eliminates the instability as the main drawback of prepregs. Diethylenetriamine was used as a low-temperature curing agent in the off-stoichiometry ratio for pre-curing and dicyandiamide was used as a latent curing agent for final curing

The manufacturing process of Sheet Molding Compounds (SMC) induces a reorientation of fibers during the flow, which influences local properties and is of interest for structural computations. Typically, the reorientation is described with an evolution equation for the second order fiber orientation tensor, which requires a closure approximation and multiple empirical parameters to describe long fibers

Nanodiamonds were annealed in a spark plasma sintering (SPS) furnace to synthesize onion-like carbon (OLC) powder, and thereafter, OLC-reinforced titanium (Ti) matrix composites with 0.1–1.0 wt% OLCs were fabricated through SPS. Experimental results showed that OLCs were partially in-situ reacted with the Ti matrix forming nano- to submicron TiC particles and some OLCs were retained after the SPS processing

This study is devoted to the damage characterization of Non-Crimp Fabric (NCF), 2D plain-woven (2D-PW) and 3D orthogonal plain-woven (ORT-PW) carbon/epoxy laminates, subjected to compression after multiple-impact loading, using Acoustic Emission (AE). The ultrasonic C-scan images showed that the interlaminar damage area induced by the single and 3-impact in ORT-PW architecture is 3 and 2 times smaller

Graphene (Gr) is one of the most preferred reinforcement for polymer matrix, due to its large surface area. However, poor dispersion, due to stacking of Gr sheets, restricts their potential as reinforcement. In the present study, exfoliation of multi-layered graphene sheets is achieved in the presence of nanodiamond (ND), using ultrasonication. High-resolution electron micrographs clearly reveal the

Natural materials represent ideal biomimetic models for materials design. However, the sophisticated natural hierarchical architectures are rather difficult to be implemented in synthetic FRCs and components through classic manufacturing methods. We propose a new method, called squeeze-winding (SW), specifically designed for the fabrication of FRC-tubes with a bone-inspired internal structure. SW represents

Conventional randomly-oriented Tow Based Discontinues Composites (TBDCs) are materials which combine good mechanical properties, lightweight and high manufacturability, and are therefore interesting for high-volume transport industries. This paper proposes, designs and successfully demonstrates a pathway to produce TBDCs with outstanding stiffness and tensile strength, by using ultra-thin tapes of

A single-stage peel method was employed to determine the relationship between key processing parameters and tack for a standard aerospace carbon/epoxy prepreg subjected to various levels of room-temperature out-time. The temperature-dependent viscoelasticity of the resin was studied using parallel plate rheometry and modelled using a simple Arrhenius equation. Differential scanning calorimetry and

Bilayer biodegradable, eco-friendly films were prepared by co-extrusion film blowing, coupling polylactic acid (PLA) and Bio-flex ® (BIO). Furthermore, in the PLA layer, carvacrol (CRV) was added as a natural antimicrobial additive, whereas a nanoclay (D72T) was integrated to protect CRV from volatilization and to modulate release. The materials were analyzed by morphological, chemical-physical, mechanical

Design an architecture with the ability to improve breakdown strength has critical role to play for performance enhancement in energy storage capability. In this work, we report that the composite films with loaded with one dimension (1D) core-shell structured NaNbO3@SiO2 nanowires ([email protected]2 NWs) are prepared and achieved significantly performance improvement in energy storage capability

Graphene oxide (GO) prepared by Hummers’ method possesses many structural defects which decrease its conductivity and limit its application in electromagnetic interference (EMI) shielding. Highly exfoliated GO with less defects (LGO) was prepared by a combination of less oxidant dosage (only 1/3 of the original dosage) and ultrasound-assisted Hummers’ method. The sulfonated reduced LGO (S-rLGO) was

This study examines the use of alkenyl succinic anhydride (ASA)-surface treated calcium carbonate as a functional mineral additive for application in wood fiber (WF)-reinforced PLA composites. The influence of addition quantity on the material properties of PLA composites with 40 wt.% fiber reinforcement was examined at mineral addition levels of 10 wt.%, 20 wt.% and 30 wt.%, respectively. The benefits

A robust super-hydrophobic coating was constructed on the surface of urea-formaldehyde (UF) foams through a facile immersion process in SiO2 nanoparticle-dispersed ethanol solution with dodecyltrimethoxysilane (DTMS) as compatibilizer. By introduction of DTMS, strong hydrogen bonding interaction formed between SiO2 coating and UF foam. The UF-g-SiO2/DTMS foam showed a water contact angle (CA) of 157

Ultra-high temperature metal matrix composites are to be constructed using a sufficiently strong refractory matrix. Oxide fibres are primary candidates to reinforce molybdenum matrix by the internal crystallisation method. However, strong molybdenum alloys have not been used as the matrix until recently because the matrix preparation requires the alloys in form of foil and wire, which are not available

Honeycomb core sandwich structures are co-cured to bond partially cured thermoset prepreg facesheets with an adhesive layer to either side of the honeycomb core under a prescribed pressure and temperature cycle in an autoclave. Defects such as porosity and poorly formed fillets of the adhesive bond-line can compromise the mechanical properties of the sandwich structure. High defect levels during the

The use of grid nano-indentation as a full-field measurement tool to investigate the properties of heterogeneous materials is described. Contrarily to the reported approaches which rely on statistical analysis, the mechanical properties fields are analyzed herein relying on a topological description of the sample. The spatial convolution function is approached using Hertz contact theory, and the obtained

Thermoplastic composite overmoulding is an integrated process to manufacture components with combined continuous and short fibre reinforcements. These components benefit from high intrinsic mechanical properties, geometric complexity and low production cycle times. In this study, ribbed plates were manufactured by overmoulding short-fibre CF/PPS (carbon fibre/polyphenylene sulphide) material onto continuous

Control of nanoparticle distribution in polymer matrices is a key factor for designing highly conductive nanocomposites. Here, polypropylene (PP)/aluminum oxide (Al2O3) nanocomposites with a continuous segregated structure were designed. Al2O3 nanoparticles were initially distributed in the polyolefin elastomer (POE) phase of PP/POE/Al2O3 with a co-continuous structure. Selective extraction of the

In this study, X-ray computed tomography was used to detect flow paths and the distribution of melamine resin in thermally-modified and subsequently plasma-treated beech veneers. By introducing iodide as a contrast agent, the melamine resin deposition in veneer samples could be visualized and quantified. The investigations showed that the deposition of melamine resin within the lumina and cell walls

Enhancing the energy density and discharge efficiency of dielectric poly(vinylidene fluoride) (PVDF) has long been a challenging task to realize their practical application as advanced electrostatic capacitors. Herein, in this work, we demonstrated a facile yet effective approach to simultaneously strengthen the energy density and discharge efficiency of PVDF through the synergy of optimized fabrication

Semi-consolidated thermoplastic tapes were produced by spreading flax and polypropylene matrix fibres using a newly developed technology. This lightweight tape was structurally stable and contained 38% flax fibres by volume. The tapes were processed in unidirectional and woven fabric format for composite fabrication. We found that the flax/PP tape-based composites had 60-110% higher flexural modulus

Natural materials usually have excellent performance for their special structures. Learning from the nature may catalyze the creation of artificial composites with unprecedented performance and functionalities. To realize this bio-inspired design idea on nano-carbon reinforced metal matrix composites, it is indispensable to understand and quantify the design principles of natural materials and consider

We investigated how temperature and relative humidity affects the electrical resistance of reinforcing carbon fibers in polymer composites. We used hybrid composites in which a tight, carbon fiber roving was laminated inside glass fiber-reinforced epoxy specimens. The electrical resistance of the carbon fibers was monitored continuously while the temperature or relative humidity was varied. The specific

This study investigates the influences of dissolved gasses on vacuum assisted resin infusion, providing a methodology which can be applied to assist in the development of robust high-performance infusion manufacturing processes. Resin degassing pressure was found to be influential on the effectiveness of degassing. Pressures under 5mBar are recommended to ensure rapid and thorough removal of dissolved

Dielectric polymer composites are promising candidates for pulsed power capacitors. Enhanced dielectric performance is usually achieved at the expense of high filler loadings. Herein, we report the realization of significantly enhanced dielectric performances in epoxy composites with ultralow BaTiO3 loadings via constructing hollow-structured BaTiO3 frameworks with hierarchical interfaces in epoxy

The rapid development and massive consumption of rigid polyurethane foams (RPUF) has drawn attention to their fire safety related problems, such as the heat release and notable generation of smoke and toxic gases in fire. Three novel types of carbon-encapsulated transition metal oxide microparticles, [email protected], Fe2O3@C and Cu2[email protected]2O3@C, were prepared via a simple hydrothermal method

A ferroelectric ceramic barium titanate (BaTiO3, BT) layer and an interfacial agent polydopamine (PDA) as the shells are coated on the cobalt ferrite (CoFe2O4, CFO) nanoparticles successively to fabricate the interfacial compatibility of this magnetic oxide. Subsequently, the coated nanoparticles are compounded with ferroelectric poly(vinylidene fluoride-trifluoro ethylene) (P(VDF-TrFE)) matrix to

Optically transparent tough cellulose nanofiber (CNF) reinforced composites were successfully prepared through a simple Pickering emulsion method. The emulsions of CNFs, acrylic resin monomer and water were vacuum filtered to form mats, and the mats were hot-pressed, and UV-cured. Hierarchical CNF networks where the homogenously-dispersed CNFs formed a network surrounding resin droplets in the composites

Laminar carbon fibre reinforced polymer (CFRP) composites contain inherent weak ply interfaces due to the lack of through-thickness fibre reinforcement. In this study, all ply interfaces were interleaved with ultra-thin (13 μm) non-woven short aramid fibre (SAF) veils to generate across ply fibre bridging, formed in-situ by movements of free fibre ends during the composite forming process. The toughening