Effect Of Fiber Architecture Research Articles

Sinusoidally architected helicoidal composites inspired by the dactyl club of mantis shrimp

ABSTRACT The impact region of the dactyl club of mantis shrimp features a rare sinusoidally helicoidal architecture, contributing to its efficient impact-resistant characteristics. This study aims to attain bioinspired sinusoidally architected composites from a practical engineering way. Morphological features of plain-woven fabric were characterized, which demonstrated that the interweaving warp and weft yarns exhibited a sinusoidal architecture. Interconnected woven composites were thus employed and helicoidally stacked to achieve the desired structure. Quasi-static three-point bending and low-velocity impact tests were subsequently performed to evaluate their mechanical performance. Under three-point bending condition, the dominant failure mode gradually changed from fiber breakage to delamination with the increase in the pitch angle. Failure displacement and energy absorption of the helicoidal woven composites were, respectively, 43.89% and 141.90% greater than the unidirectional ones. Under low-velocity impact condition, the damage area of the helicoidal woven composites decreased by 49.66% while the residual strength increased by 10.10% compared with those of the unidirectional ones, exhibiting better damage resistance and tolerance. Also, effects of fiber architecture on mechanical properties were examined. This work will shed light on future design of the next-generation impact-resistant architected composites.

Effect of fiber architecture on tension–tension fatigue behavior of bolted basalt composite joints

The effect of fiber architecture, i.e., unidirectional (UD) vs. multi-directional (MD), on the tension–tension fatigue behavior of bolted double-lap basalt composite joints was experimentally investigated. The fatigue load-life (F-N) curves of MD and UD bolted joints were established and fatigue degradation was characterized by cyclic displacement, cyclic energy dissipation, cyclic stiffness, and self-generated heat. The failure mechanisms and fatigue life of MD and UD bolted joints during fatigue were discussed and further compared to similar adhesively bonded joints. The results showed that the MD bolted joints exhibited much longer fatigue life than UD bolted joints, however, the rapid damage initiation and propagation in the former led to a slightly steeper slope of the F-N curve. The fatigue life of the MD bolted joints was much shorter than that of the bonded joints mainly due to the lower static resistance of the former. However, the slope of the F-N curve of the MD bolted joints, resulting from fiber-dominated fatigue damage, was much flatter than that of the bonded joints caused by polymer-dominated creep-fatigue interaction.

Dynamic mechanical analysis of glass fiber reinforced epoxy filled nanoclay hybrid composites

In this work, dynamic mechanical analysis (DMA) of hybrid composite material made up of glass fiber reinforced epoxy polymer filled with nanoclay particles is investigated. The effect of fiber architecture, orientation and concentration on DMA properties of hybrids is studied. Three different types of glass fiber mats were chosen, namely, unidirectional glass fiber (UD-GF), woven glass fiber (W-GF) and chopped strand mat glass fiber (CSM-GF) and they were individually reinforced in epoxy polymer matrix at three different varying concentration (25 wt%, 50 wt% and 75 wt%). The nanoclay particles were added as filler material and its concentration was varied from 1 to 5 wt% in all the hybrid series. In UD-GF reinforced hybrid, the fibers are oriented at different orientation (0° to 90°) with respect to loading condition and the DMA properties was evaluated. The structure and fiber–matrix interface morphologies were examined by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) analysis. The effect of interface properties on DMA properties is studied by theoretical and Cole-cole methods. The result shows that the DMA properties such as storage module, glass transition temperature (Tg) and Tanδ curve (peak and width) were affected by both the concentration and morphology of glass fiber reinforcement and the nanoclay fillers. In general, nanoclay reinforcement in glass fiber reinforced epoxy composites improves the hybridization effect and positively improves the DMA properties.

Creep properties of melt infiltrated SiC/SiC composites with Sylramic™‐iBN and Hi‐Nicalon™‐S fibers

AbstractIsothermal tensile creep tests were conducted on 2D woven and laminated, 0/90 balanced melt infiltration (MI) SiC/SiC composites at stress levels from 48 to 138 MPa and temperatures to 1400°C in air. Effects of fiber architecture and fiber types on creep properties, influence of accumulated creep strain on in‐plane tensile properties, and the dominant constituent controlling the creep behavior and creep rupture properties of these composites were investigated. In addition, the creep parameters of both composites were determined. Results indicate that in 2D woven MI SiC/SiC composites with Sylramic™‐iBN or Hi‐Nicalon™‐S fibers, creep is controlled by chemical vapor infiltration (CVI) SiC matrix, whereas in 2D laminated MI SiC/SiC composites with Hi‐Nicalon™‐S fibers, creep is controlled by the fiber. Both types of composites exhibit significant variation in creep behavior and rupture life at a constant temperature and stress, predominantly due to local variation in microstructural inhomogeneity and stress raisers. In both types of composites at temperatures >1350°C, residual silicon present in SiC matrix to reacts with SiC fibers and fiber coating causing premature creep rupture. Using the creep parameters generated, the creep behaviors of the composites have been modeled and factors influencing creep durability are discussed.

Effect of fiber architecture on the impact resistance of composite panels subjected to metallic projectile

Experiments using a single-stage gas gun were conducted to evaluate the resistance of three types of composite panels to high-velocity impacts from metallic projectiles: panels reinforced with unidirectional tape or formed from plain-woven fabric or two-dimensionally braided fabric. The critical penetration velocity, deformation, and failure morphologies were examined by virtue of high-speed photography, 3D digital image correlation technology and non-destructive testing methods. In addition, a normalized quantity was introduced to assess the energy absorption capacity of the panels. Laminates stacked by angle-ply unidirectional tapes contained impacts at higher velocities than other panels, and the energy absorption capacities of the plain-woven and braided composite panels are comparable. The results provide insights into the impact failure behavior of composite panels and can aid in the selection of materials for aeroengine casings.

Experimental and statistical analysis of strength of glass fiber reinforced polymer composite for different fiber architecture

AbstractIn the present study, the effect of fiber architecture on mechanical properties of E‐glass fiber reinforced polymer composite has been investigated experimentally. The influence of fiber volume fraction on strength of composite has also been predicted using second order polynomial regression models. The glass fibers were arranged in different architecture like unidirectional continuous, unidirectional discontinuous, short randomly oriented, transversely aligned, and woven for preparation of composites. The tensile and flexural tests were performed as per ASTM D3039 and ASTM D790, respectively. The experimental results of tensile and flexural properties of composites have been discussed. Results predicted by the regression models are in good agreement with experimental results which indicate the goodness of fit and the models are statistically significant.

The Effect of Polyethylene Glycol on Polycaprolactone Electrospun Scaffolds: Morphology, Mechanical Properties, and Nerve Growth Factor Delivery Profile

Electrospinning is a promising technique to generate scaffolds for delivery systems and nerve tissue engineering. This study aimed to investigate the suitability of polyethylene glycol (PEG) as an agent to prolong circulation time in the delivery of nerve growth factor (NGF) encapsulated into polycaprolactone (PCL) electrospun fibers. Three molecular weights (400, 1500, and 35000 Da) and concentrations (1, 5, and 10% ratio to PCL) of PEG were studied. The effect on NGF from the scaffolds was evaluated by neuronal differentiation using PC12 cells. Scaffolds were characterized for their architecture by Scanning Electron Microscopy (SEM) and for their mechanical properties. Cytotoxicity was evaluated by MTT and agarose overlay methods. The effect of fiber architecture on PC12 morphology was also investigated. Nanofibrous hybrid mats were obtained for all PCL/PEG blends tested. The addition of PEG caused a reduction in the average due to the increased stretching ability over the electrospinning process. This reduction on fiber diameter showed impact on mechanical properties of the fibrous scaffolds, i.e. lower tensile strength and elongation were observed for scaffolds with 5% and 10% PEG. The co-lyophilization of NGF with PEG prior to nanofiber production improved the delivery profile of NGF, stimulating neuronal cell differentiation even after 28 days of continuous release.

Effect of fiber architecture on the residual strength of laminate glass fiber-reinforced polymer composites after impact

Glass fiber-reinforced polymer (GFRP) composites are widely applied in automotive and shipbuilding industry. However, impact damage is unavoidable to the composites during production or service, and the evaluation of performance degradation after impact is necessary. The architecture of the fiber preform shows significant influence on the impact damage behavior of GFRP. The present work focused on the influence of preform structure on damage evolution and residual load-bearing capability of the composites. The microstructure and the residual strength after the impact of GFRP with plain-weave preform structure and cross-ply preform structure have been investigated, respectively. The low velocity impact primarily caused matrix cracking and delamination, but unobvious fiber failure to GFRP. More impact-damaged plies were detected in cross-ply composites than plain-weave composites after impact. It indicated that plain-weave preform structure owes better impact damage shielding capability. However, the GFRP with plain-weave preform structure exhibited better impact resistant ability under low impact energy but less residual strength under high impact energy, compared with the GFRP with cross-ply preform structure. The interaction between the warp and weft fibers made the plain-weave composites absorbing more energy in a single ply, which was the reason for the plain-weave composites to exhibit excellent damage shielding performance but poor residual strength under high impact energy.

The effect of fiber architecture on the mechanical properties of carbon/epoxy composites

Abstract The main aim of this study was to get a better knowledge of mechanical properties of carbon fabric reinforced epoxy (CF/Ep) composites. The selected mechanical properties of the CF/Ep composite with different fiber architectures (T300CF/Ep, T700CF/Ep and T800CF/Ep) are investigated for indentation, in-plane, tensile and bending loads. All composites were fabricated with equal weight percentage of carbon fiber and similar consolidation process using hand layup procedure followed by compression moulding method. Experimental results showed that the effect of fiber weave structure on mechanical properties of the CF/Ep composites is more obvious than that in neat epoxy. Both tensile and flexural results showed that high strength carbon fiber (T800) has evident strengthening effects on the tensile and bending load response of CF/Ep composites. The fiber architecture marginally affects the density and severely affects strength and deformation of composites. T300CF/Ep and T800CF/Ep composites are nearly linear up to final brittle fracture while T700CF/Ep system exhibit non-linearity before failure. Furthermore, it is seen that composite performance is dictated by inherent properties of carbon fiber and weaves structure. Even with fiber flaws, stress concentrations, the weaving pattern is beneficial because it makes composites to be very less subtle to flaws. These characteristics are addressed systematically with consideration of numerical aspects of fibers strength and critical defects formation. The significant developments in the mechanical properties of composite systems are further assisted using scanning electron microscopy

Effect of fibre architecture on the specific energy absorption in carbon epoxy composite tubes under progressive crushing

This paper presents the progressive crushing performance of composite tubes with varied fibre architecture. The effect of lay-up configuration and influence of percentage of unidirectional (UD) and woven fabric (WF) fibre architectures on the specific energy absorption (SEA) is investigated using experiments. Composite tubes with internal diameter 42 mm and wall thickness to diameter of 0.05 were manufactured for a range of specimens with different ratios of axial and hoop fibres. The samples were chamfered at an angle of 70°. Progressive crushing of specimens under quasi-static (20 mm/min) and dynamic (4.48–6.7 m/s) loading were performed. A new factor Axial Fibre Mass Fraction (AFMF) was introduced to describe the mass fraction of axial fibres to reflect upon the SEA response. To investigate the influence of AFMF and loading rate on the crushing mechanism of composite tubes, computer tomography (CT) was additionally. The calculated SEA for different loading conditions indicate a drop of 10%–20% for dynamic cases depending on the fibre architecture of the samples. The CT-scans present a relationship between debris length and AFMF. The average length of debris decreases with the increase of AFMF which indicates more intense fibre breaking, reduced integrity of the ‘petals’ and hence increased SEA.

Effect of fiber architecture on tensile fracture of 3D woven textile composites

3D woven composites offer higher damage tolerance and resistance to delamination. Understanding how the architecture influences the tensile failure of the composite is imperative to ensure proper use. In this work the tensile response of two different woven architectures is investigated to determine how failure initiates in the composite in each case. Z-fiber reinforced materials were compared against layer-to-layer architectures. Details of the failure were examined both through digital image correlation and also through post inspection analysis using a dye penetrant. The results show that there is an architecture dependent strain field and these localizations lead to the onset of failure in these materials.

Fire performance of continuous glass fibre reinforced polycarbonate composites: The effect of fibre architecture on the fire properties of polycarbonate composites

The fire performance of polycarbonate resin and the role of glass fibre reinforcement in altering the fire performance was investigated. Three different fibre weaves with comparable surface density, plain, twill, and unidirectional glass fabrics, were used as reinforcements. E-glass fabrics were solution-impregnated with polycarbonate/dichloromethyl, laid up, and compression-moulded to consolidate the glass fibre reinforced polycarbonate composite. Cone calorimetry tests with an incident radiant flux of 35 kW/m2 were used to investigate the fire properties of polycarbonate resin and its composites. Results showed that glass fibre reinforcement improves polycarbonate performance by delaying its ignition, decreasing its heat release rate, and lowering the mass loss rate. The three fibre weave types exhibited similar time to ignition. However, unidirectional fibre had a 35% lower peak heat release rate followed when compared to plain and twill weave fibres.

An investigation into the effects of fiber architecture on the mechanical behavior of woven preforms

This study attempts to analyze the behavior of different types of woven composite preforms (i.e. plain, twill, and satin) under distinct loading conditions. To this end, fabric elements are modeled using discrete finite element approach. Different loading scenarios such as intra-ply shear, in-plane tension, and simultaneous intra-ply shear and in-plane tension loads are applied to the fabric elements. TexGen software is utilized to develop the geometric model of the fabric elements. Subsequently, the geometric model is exported to ABAQUS FE package and mechanistic analyses are conducted. The FE results reveal that under the same loading conditions, the in-plane tensile stress induced in plain weave elements has the minimum value compared to twill and satin elements. Having said that, the intra-ply shear resistance of the plain element is larger than the other weave types. What’s more, the behavior of the fabric elements under simultaneous intra-ply shear and tension loading scenarios are studied that discloses almost the similar response for all weave types.

Effect of fibre architecture on the tensile and impact behaviour of ductile stainless steel fibre polypropylene composites

The high stiffness (∼193GPa) and high strain-to-failure (∼20%) of annealed stainless steel fibres present an opportunity to design ductile structural composites. In this research, the effect of the weave architecture on the tensile and impact behaviour of ductile stainless steel fibre/PP composites is investigated. Composites with three different weave architectures are compared: a quasi-unidirectional weave, a basket weave and a satin weave. The tensile test results show that all weave architectures show the same composite strain-to-failure, despite the difference in crimp. The composite with the basket weave (high crimp) has much lower stiffness and yield stress in comparison with the other two composites. This is attributed to significant out-of-plane deformations observed during the tensile test. The penetration impact results show that the high ductility of stainless steel fibre composites in tensile tests is transferred into excellent impact performance.

Effect of fiber architecture and density on the ablation behavior of carbon/carbon composites modified by Zr–Ti–C

Three carbon/carbon (C/C) composites modified by Zr–Ti–C, with different fiber architecture in preforms and the same density, were prepared using chemical vapor infiltration and reactive melt infiltration methods. Two other samples with the same architecture in preforms and different density were also fabricated by the same methods. Their ablation behaviors were examined by oxy-acetylene flame. The results showed that the samples with chopped web needled perform had better ablation resistance than that of the samples with needle-integrated and fine-weave pierced perform. In the models of ablation behaviors, the sealing time of pores and gaps on the ablated surfaces has been defined to indirectly estimate the ablation property. The analysis of models also indicated that high density of the composites and appropriate small diameter of bundles of carbon fibers led to the short sealing time and good ablation resistance of the C/C–carbide composites.

Candida albicans adhesion on reinforced polymethylmethacrylate denture resin: effect of fibre architecture and exposure to saliva

Fiber-reinforced composites (FRC) are used to reinforce the prosthetic and restorative appliances. This may result in the exposure of the FRCs which may affect the adherence of microorganisms. This study evaluated the adhesion of Candida albicans to a denture base resin (N = 48), reinforced with E-glass FRCs with different architectures [unidirectional (n = 16) and woven (n = 16)], when exposed to either saliva or distilled water. Specimens without FRC reinforcement served as control (n = 16). After fiber surfaces were exposed, half of the specimens (n = 8/per group) were treated with saliva, the other half was stored in distilled water prior to C. albicans adhesion. The adhered microorganisms were counted under an optical microscope and the data were analyzed. When exposed to distilled water or saliva, specimens with unidirectional (5403.4 cells/cm(2) and 5013.4 cells/cm(2) , respectively) (p = 0.202), woven fibers (4053.5 cells/cm(2) and 3726.6 cells/cm(2) , respectively) (p = 0.283) and specimens without fibers (2250 cells/cm(2) and 2006.8 cells/cm(2) , respectively) (p = 0.423) showed C. albicans adhesion, being not significant. In general, all the specimens exposed to saliva showed 3582.2 cells/cm(2) C. albicans adhesion, while specimens exposed to distilled water showed 3902 cells/cm(2) C. albicans adhesion, yet being not significant (p = 0.436). Regarding fiber type, C. albicans adhesion was significantly affected by the exposed FRC architecture with more favorable results for woven fibers (p < 0.001). Polymethylmethacrylate without FRCs collected less C. albicans. The presence of saliva seems to reduce the adhesion.

The Effects of Fiber Architecture and Fiber Surface Treatment on Physical Properties of Woven Sisal Fiber/Epoxy Composites

The aim of this work was to investigate the effects of fiber architecture and fiber surface treatment on flexural and impact properties of woven sisal fiber/epoxy composites. The woven sisal fibers with three different weave types including plain weave (P-weave), harness satin weave (S-weave) and right hand twill weave (R-weave) were used. For untreated fiber/epoxy composites, the fiber contents in the composite were 0, 5, 10 and 15% by weight (%wt). The untreated S-weave sisal fiber/epoxy composites showed the best overall properties and the composites with 15% fiber loading showed the highest properties. When compared to pure epoxy, flexural strength, flexural modulus and impact strength of the composite with 15% wt fiber increased by 4.5%, 60.6% and 150% respectively. Therefore, the composite of 15% wt silane treated S-weave and epoxy was prepared in order to study the effect of fiber surface treatment. The results showed that the composite containing 15% wt silane treated fiber possessed nearly the same properties with the untreated fiber/epoxy composite.

Effects of Fiber Architecture on Matrix Cracking for Melt‐Infiltrated SiC/SiC Composites

The matrix cracking behavior of slurry cast melt‐infiltrated SiC matrix composites consisting of Sylramic‐iBN fibers with a wide variety of fiber architectures were compared. The fiber architectures included 2D woven, braided, 3D orthogonal, and angle interlock architectures. Acoustic emission was used to monitor in‐plane matrix cracking during unload–reload tensile tests. Two key parameters were found to control matrix‐cracking behavior: the fiber volume fraction in the loading direction and the area of the weakest portion of the structure, that is, the largest tow in the architecture perpendicular to the loading direction. Empirical models that support these results are presented and discussed.

Effect of Fibre Architecture on the Falling Weight Impact Properties of Hemp/Epoxy Composites

The aim of this work is studying the falling weight impact properties of three different types of hemp/epoxy composites, two of which were realised using loose hemp fibres disposed either unidirectionally (LU laminate) or in a 0/90 (LC laminate), while the third one has been obtained using hemp mat (M laminate). The maximum fibre volume which was possibly introduced using hand layup was 55 vol.% for LU, 52 vol.% for LC and only 43 vol.% for M laminate. In practice, the aim of this investigation would be evaluating whether disposing loose hemp fibres in a mat, an operation which results in the reduction of the volume of reinforcement introduced, would yield lower falling impact properties or not. Quasi-static tests results show that the best performance, but also the largest scattering in properties is obtained from the unidirectional composites (LU): this suggests the fundamental role played by fibre orientation in these materials. In contrast, the study of impact hysteresis cycles suggest that, despite the limitations owed to the presence of through thickness fibres and the lower amount of fibres introduced, hemp mat laminates (M) are superior in terms of impact properties. In particular, impact hysteresis cycles involve, in the case of M laminates, a higher stiffness in the linear-elastic phase of impact, followed by a hardly detectable load drop, and a very large rebound energy, released at quasi-constant rate after penetration. As a result, a larger amount of energy is absorbed during impact on hemp mat laminates than on the loose hemp laminates.

Effect of fiber architecture on flexural characteristics and fracture of fiber-reinforced dental composites

Objective The aim of this study was to compare and elucidate the differences in damage mechanisms and response of fiber-reinforced dental resin composites based on three different brands under flexural loading. The types of reinforcement consisted of a unidirectional E-glass prepreg (Splint-It from Jeneric/Petron Inc.), an ultrahigh molecular weight polyethylene fiber based biaxial braid (Connect, Kerr) and an ultrahigh molecular weight polyethylene fiber based leno-weave (Ribbond). Methods Three different commercially available fiber reinforcing systems were used to fabricate rectangular bars, with the fiber reinforcement close to the tensile face, which were tested in flexure with an emphasis on studying damage mechanisms and response. Eight specimens ( n = 8) of each type were tested. Overall energy capacity as well as flexural strength and modulus were determined and results compared in light of the different abilities of the architectures used. Results Under flexural loading unreinforced and unidirectional prepreg reinforced dental composites failed in a brittle fashion, whereas the braid and leno-weave reinforced materials underwent significant deformation without rupture. The braid reinforced specimens showed the highest peak load. The addition of the unidirectional to the matrix resulted in an average strain of 0.06 mm/mm which is 50% greater than the capacity of the unreinforced matrix, whereas the addition of the braid and leno-weave resulted in increases of 119 and 126%, respectively, emphasizing the higher capacity of both the UHM polyethylene fibers and the architectures to hold together without rupture under flexural loading. The addition of the fiber reinforcement substantially increases the level of strain energy in the specimens with the maximum being attained in the braid reinforced specimens with a 433% increase in energy absorption capability above the unreinforced case. The minimum scatter and highest consistency in response is seen in the leno-weave reinforced specimens due to the details of the architecture which restrict fabric shearing and movement during placement. Significance It is crucial that the appropriate selection of fiber architectures be made not just from a perspective of highest strength, but overall damage tolerance and energy absorption. Differences in weaves and architectures can result in substantially different performance and appropriate selection can mitigate premature and catastrophic failure. The study provides details of materials level response characteristics which are useful in selection of the fiber reinforcement based on specifics of application.