Fabric Composite Laminates Research Articles

Mechanical properties of basalt fiber/ epoxy resin composites

This paper presents a study regarding the obtaining, characterizing and mechanically testing a new laminar composite material, consisting of epoxy resin reinforced with basalt plain fabric. The composites were obtained by manual lay-up, cross-link stage being developed by pressure molding in a hydraulic press. Rectangular plates were obtained and cut into samples with specific shapes, for the mechanical tests (tensile, three-point bending and compression). After testing, the fracture zone was analyzed using optical microscopy to observe the behavior of the composite following the mechanical stresses applied (fracture mechanism, voids presence and fiber delamination identification). Due to the low costs and non-hazardous nature, basalt fibers can be a serious competitor in the production of laminar composites that could successfully replace ordinary glass fiber composites. The mechanical properties in tensile, three-point bending, and compression of epoxy-resin-impregnated basalt fiber composites are comparable and even exceed those of widely used epoxy-resin-impregnated fiberglass composites.

Performance and Life Cycle Assessment of Composites Reinforced with Natural Fibers and End-of-Life Textiles

The growing need for materials that are eco-friendly and sustainable in the industrial sector has shifted focus from synthetic fossil to natural fibers, alongside the utilization of recycled polymer textiles. This research introduces a novel method for using end-of-life textiles, such as polyester and polyamide fabrics, in the production of composite materials, aiming to lessen textile waste and enhance material longevity. The mechanical attributes of flax fabric (FF), flax–recycled polyamide fabric (F/RPA), and flax–recycled polyester fabric (F/RPES) composite laminates are assessed through tensile, flexural, interlaminar shear, and Charpy impact tests. The study revealed that the addition of end-of-life synthetic fibers improves tensile strength, while the trend in modulus values suggests that flax provides a high degree of stiffness to the composites, which is moderated by the addition of synthetic fibers. This effect is consistent across both tensile and flexural testing, although the impact on stiffness is more significant in bending. The inclusion of polyester fibers in the composite laminate resulted in significant enhancements, with an 11.1% increase in interlaminar shear maximum force, a 17.4% improvement in interlaminar shear strength, and a 67.1% rise in un-notch impact energy, compared to composites made with only flax fiber (FF). The microscopic examination uncovered the internal structure and demonstrated a clear, strong bond between the polyester and polyamide fiber layers with the flax fibers. Additionally, the life cycle assessment revealed that the F/RPES composite had less environmental impact than FF and F/RPA in all 18 categories analyzed. This indicates that the environmental footprint of producing F/RPES is smaller than that of both FF and F/RPA.

The Influence of e-glass epoxy composite laminate material application on the crack pattern of cylinder concrete column cross-section

In order to better understand the phenomenon of applying GEC reinforcement to RCC based on the percentage of surface crack pattern (PCP), this research will use e-glass epoxy composite laminate (GEC) to obtain the damage pattern of reinforced concrete column specimens (RCC) utilizing GEC. Additionally, it will compare the splitting tensile strength (STS) and SCP. In accordance with ASTM C496 guidelines, the RCC specimens used in this investigation had a cylindrical shape and measured 150 mm in length and 50 mm in diameter. GEC material, consisting of 0–4 layers of woven e-glass fiber sheets, was applied as an extra layer on top of the RCC. In compliance with ASTM C496 guidelines, a Universal Testing Machine (UTM) was used to perform the split tensile test. With the aid of Adobe Photoshop software, the Histogram approach was used to calculate the crack pattern's proportion. The study's findings demonstrated that the specimens reinforced with four layers of GEC exhibited the highest damage pattern. This suggests that the reinforced specimens must be subjected to a sizable load in order to be damaged. Hence, the damage that occurs in the specimens can be lessened by applying GEC layers on RCC. Further information about the performance of RCC reinforced with GEC is also provided by a comparison of the splitting tensile strength and the percentage of fracture pattern

Couple effects of multi-impact damage and CAI capability on NCF composites

Abstract In this study, the mechanical properties of non-crimp fabric (NCF) composite laminates under low-velocity impact and compression after impact (CAI) tests were studied by Scanning electron microscopy (SEM) and Digital image correlation (DIC) techniques. The impact response under different impact times, impact angles, and impact distance is studied. Similarly, in CAI test, DIC technique is used to reveal the whole process of NCF composite compression failure, and SEM is used to reveal the microscopic failure form. The experimental results show that the impact damage process of NCF composites has strong directivity. The concrete manifestation is that the internal failure will extend along the paving direction at the failure layer. The peak load generated under 20 J impact energy is about 1/2 of that under 40 J impact energy. The impact distance is one of the important factors affecting the coupling effect of multiple impacts, and the impact angle has little effect on the internal damage extension. The proportion of internal damage area also supports the relevant view, that is, the average difference in the proportion of internal damage area under different impact distance is about 5%, while the average difference in the proportion of internal damage area under different impact angles is about 3%. During the compression process, the main failure mode is shear failure and the failure mode is brittle fracture. The oblique fracture occurs only when the oblique is 45° and the impact distance is large (50 mm). The impact angle has little effect on the residual compression performance of NCF.

Experimental investigation on the ballistic performance of B4C/Aramid/UHMWPE composite armors against API projectile under different temperatures

In the design of lightweight composite armor, it is crucial to consider the challenging conditions of extreme environments encountered during service. This study proposes to investigate the effect of temperature on the ballistic performance of a B4C/aramid III/UHMWPE composite armor system against 12.7 mm armor-piercing incendiary (API) projectiles with an impact velocity of ∼500 m/s. A series of ballistic experiments were conducted under low temperature (-40 ℃), high temperature (+70 ℃), and room temperature (+20 ℃) respectively considering two shooting distances of 100 m (long-range shooting) and 30 m (close-range shooting). The structural failure modes and associated mechanisms were identified and analyzed in detail from both macroscopic and microscopic scales. The experimental results indicate that the designed composite armor is believed to perform better than the existing design schemes in resisting the 12.7 mm half-speed API projectile on the basis of similar or less areal density. The ballistic performance of the composite armor system is significantly enhanced at low temperatures and weakened at high temperatures in terms of structural damage levels and backplate bulge deformation. The decrease in shooting distance transformed the panel failure mode essentially from non-penetration to penetration under room and high temperatures, whereas the specimens under low temperatures could prevent penetration. Both the ceramic and composite laminate materials are affected by temperature and show different microscopic damage modes, indicating the damage mechanism changes at the microscopic level. These findings provide valuable insight into the design of lightweight composite armor systems to adapt to extreme service environments.

Bending, Tensile and Water Absoption Test of Corn Husk and Glass Fibre Reinforced Composite For Different Composition

Now a day, there is a huge trend in research and development of bio-based products which have a wide variety of replacement for naturally existing materials. The current research intends to determine the qualities of a composite laminate material consisting of maize husk and glass fibre. The composite is created by alternately overlaying glass fibre cloths on corn husk fibre layers. The required composition and thickness are achieved by calculation of number of the layer of each fibres. The epoxy resin and hardener by weight is mixed in the ratio 10:1 respectively. It is poured between the layers of the composite to generate adhesion. Hand lay-up technique is adopted in manufacturing of the material and the material is pressed for certain duration using nut and bolt template assembly allowing it for natural curing. The composite is been tested for bending, tensile and water absorption tests according to standards.

A novel three-layer woven fabric composite reinforced by (polyaniline + carbonyl iron) core-shell/carbonyl iron/polyaniline fillers for high-performance broadband radar absorbing structure

One of the most important applications of electromagnetic wave absorption is in stealth aircrafts and electromagnetic protection of avionic systems. The main limitations in the design of these structures are aerodynamics, thickness or weight, mechanical strength, manufacturing process, and reasonable cost. In this study, a novel three-layer woven fabric composite laminate (with a total thickness of about 3 mm) is proposed which each layer is reinforced by individual polyaniline, carbonyl iron, or (PANI + CI) core-shell fillers. The developed Non-dominated Sorting Genetic Algorithm II optimization algorithm suggests the stacking sequence of layers, the appropriate thickness of each layer, and the filler weight fraction in each layer to achieve a broadband absorption. Due to using both dielectric and magnetic absorbing fillers, this structure shows well-impedance matching and approximately absorbs 80% of the X-band (8-12 GHz) electromagnetic waves. The maximum reflection loss is about −14dB. Finally, the effect of the addition of absorbent particles on the mechanical properties has been investigated. Experimental results showed that the tensile modulus and strength decrease by about 21.5% and 20.6%, respectively, and the flexural modulus and strength reduce by 21.7% and 19.7%, respectively. However, the (PANI + CI) core-shell filler can be introduced as a high performance absorber filler because it suggests maximum reflection loss with low weight fraction compared to other fillers and consequently the minimum reduction in mechanical properties.

Optimization of a structural Acoustic Black Hole embedded in a stringer-stiffened composite laminate panel

Many modern airframes are made of composite laminate materials due to their low mass but strong loadbearing capability. Carbon fiber composite laminates allow for a strong and lightweight aircraft, but create unhealthy levels of disruptive and uncomfortable noise within the fuselage. This work looks at the possibility of a structural Acoustic Black Hole (ABH) as a passive vibration damping solution for a common stringer-stiffened airframe panel. A 1-D symmetrically damped ABH was integrated vertically into the cross section of a stringer stiffener of a composite laminate plate. A multi-objective evolutionary algorithm was employed to search for the optimal ABH dimensions in terms of the tradeoff between weight, axial linear buckling load, and integrated vibration response. Computational results predicted the ability for damped ABH-stiffeners of a certain dimension to have less vibrational response than others with comparable linear density and axial strength. Mass normalized, non-tapered and ABH-tapered preliminary panels were manufactured and tested. These results showed a capability of ABH stiffeners to decrease vibrational response in the attached skin, more prominently above their cut-on frequency. Stiffened panels were manufactured to optimized specifications and their experimental results validate the presence of an optimal ABH dimension to achieve passive vibration damping in a system with mass and structural constraints.

Tensile, bending, and impact properties of laminated carbon/aramid/glass hybrid fiber composites

Abstract In this study, hybrid (carbon, glass, and aramid) fabric epoxy composite laminates were fabricated with different layering sequences by hand lay-up. The effects of layering arrangements of laminated composite fibers on the mechanical properties of hybrid composites were investigated. Tensile, bending, and impact tests were performed to obtain the mechanical behaviors of hybrid composites. It was found that the layering sequences significantly affect the tensile, bending strength, and impact energy. As a result of the tensile tests, the highest tensile strength was obtained in the 3C + 3G combination. The highest load-carrying capacity in three-point bending tests was obtained in the 2G + 2A + 2C combination. The combination with the highest impact energy was 2C + 2G + 2A, and the lowest was 3C + 3G. It has been observed that hybrid composites containing aramid fiber absorb higher impact energy than others. The results showed that the layering sequences are essential in hybrid composites with the same fiber and layer number.

Thermal properties and mechanical behavior of hot pressed PEEK/graphite thin film laminate composites

This work studies high-performance laminate composite materials made of graphite and poly(ether-ether-ketone) (PEEK). The main objective was to enhance graphite's inherent properties by the addition of PEEK to produce materials with improved thermal and mechanical stability for high-performance applications. The composites were fabricated using a hot press method at a temperature below 310 °C. The newly formed materials were then subjected to various tests, including Scanning Electron Microscopy, Thermogravimetric Analysis, mechanical properties tests, nanoindentation tests, and X-Ray Diffraction to assess their structural, thermal, and mechanical properties. Our findings showed a substantial interfacial interaction between PEEK and graphite, indicating successful composite formation. Both three-layered PEEK/graphite/PEEK (PGP) and five-layered PEEK/graphite/PEEK/graphite/PEEK (PG)2P composites exhibited superior thermal stability at high temperatures compared to neat PEEK. Moreover, our mechanical tests demonstrated a 172% increase in ultimate tensile strength of PGP compared to neat graphite. Additionally, nanoindentation tests confirmed an increase in both Young's modulus and hardness of composites. Furthermore, XRD analysis revealed a 35.5% increase in crystallinity in the fabricated composites compared to pristine PEEK. These findings significantly contribute to the field of high-performance composite materials, confirming that the hot pressing of PEEK and graphite sheets results in enhanced thermal and mechanical properties.

Studies on the stab resistance and ergonomic comfort behaviour of multilayer STF-treated tri-component woven fabric and HPPE laminate composite material

Research related to stab-resistant armour is focused on developing a low-weight flexible stab-resistant armour. Various materials and methods have been used to reduce the overall bulk but managing the flexibility and bulk with improved stab resistance is still a challenge for the researchers. In this study, flexible stab-resistant material for stab-resistant personal protective equipments (PPEs) has been developed by using shear thickening fluid (STF) treated fabric made of multicomponent yarns and ultra high molecular weight polyethylene (UHMWPE) laminate composite. The stab resistance and comfort behaviour like flexural rigidity and areal density were investigated with respect to number of layers and different STF concentrations according to VPAM KDIW-2004 and respective standards for flexural rigidity. Laminate-Woven hybrid composite was developed to reduce the bulk of the panel while maintaining the required protection level.

Effect of sample cutting angle on mechanical properties of jute/cotton fabric epoxy composite laminates

Effect of sample cutting angle on mechanical properties of jute/cotton fabric epoxy composite laminates

Modeling and analysis of laminate structures of a pressurized hydrogen tank

Hydrogen storage involves technology development and it is one of the principal fields of improvement to enhance the use of hydrogen energy. The major problems to solve is the adequate materiel chose and the temperature control under high storage pressure. In this work, we are going to present the effects of geometry and inconstant mass flow rate on the pressure ant temperatures within a pressurized hydrogen cylinder during refueling, three laminate composite materials are used and investigate for hydrogen storage tank. The simulations are conducted using a Computational Fluid Dynamics (CFD) tool. The results show that, adding the carbon fiber laminate increases the hydrogen storage pressure. Also, the model shows that the temperature is maintained at a common level but with different distributions.

Laminar composite materials for unmanned aircraft wings

Unmanned Aerial Vehicles (UAVs) have high popularity, especially in the military field, but are now also being applied to the private and public sectors. One of the UAV components that require high material technology is the wing. The latest material technology developed as a material for unmanned aircraft wings is a composite material that has high strength and lightweight. This research aims to identify composite materials that can be used for unmanned aircraft wing structures. The method used in this research is a qualitative method with a literature study approach. The results of this theoretical study show that some of the latest composite materials that have been developed into materials for unmanned aircraft wings are Laminar Composites with a sandwich structure. Laminar and sandwich composites consist of various constituent materials such as Balsa wood fiber-glass and polyester resin, microparticles, Carbon Fibre Reinforced Polymer, polymer matrix composites reinforced with continuous fibers, Polymer matrix composites, E-glass/Epoxy, Kevlar/Epoxy, Carbon/Epoxy, woven fabrics, acrylonitrile butadiene styrene-carbon (ABS) laminated with carbon fiber reinforced polymer (CFRP) and uniaxial prepreg fabrics. Laminar and sandwich composite materials are a reference for developing unmanned aircraft wing structures that have resistant strength and lightweight.

Stochastic Evaluation of Cutting Tool Load and Surface Quality during Milling of HPL

The topic of the article concerns the mechanics of machining plastics and their machined surface. This article deals with measurements and their stochastic (probabilistic) evaluation of the force and moment loading of the machine tools and workpiece. It also deals with the quality of the machined surface in relation to its surface roughness and surface integrity. Measurements were made under different cutting conditions on a CNC milling machine using a newly designed cutter with straight teeth. The statistical evaluation is presented by bounded histograms and basic statistical characteristics that give a realistic idea of the machining process. The practical focus of the experiments is on the milling of HPL (high-pressure plastic–laminate composite material). The listed procedures can also be applied to other materials and machining methods, and can be used for numerical modelling, setting the optimum parameters of machining technology, or for the design of cutting tools. Numerical modelling and other solution options are also mentioned. We have not yet found detailed information in the literature about the milling of HPL material, and our results are therefore new and necessary.

Small-noise approximation for Bayesian optimal experimental design with nuisance uncertainty

Calculating the expected information gain in optimal Bayesian experimental design typically relies on nested Monte Carlo sampling. When the model also contains nuisance parameters, which are parameters that contribute to the overall uncertainty of the system but are of no interest in the Bayesian design framework, this introduces a second inner loop. We propose and derive a small-noise approximation for this additional inner loop. The computational cost of our method can be further reduced by applying a Laplace approximation to the remaining inner loop. Thus, we present two methods, the small-noise double-loop Monte Carlo and small-noise Monte Carlo Laplace methods. Moreover, we demonstrate that the total complexity of these two approaches remains comparable to the case without nuisance uncertainty. To assess the efficiency of these methods, we present three examples, and the last example includes the partial differential equation for the electrical impedance tomography experiment for composite laminate materials.

Fatigue life prediction and optimization of GFRP composites based on Failure Tensor Polynomial in Fatigue model with exponential fitting approach

In this study, a new fatigue life prediction and optimization strategy utilizing the Failure Tensor Polynomial in Fatigue (FTPF) model with exponential fitting and numerical bisection method for fiber reinforced polymer composites has been proposed. Within the experimental stage, glass/epoxy composite laminates with [Formula: see text], [Formula: see text], and [Formula: see text] lay-up configurations were fabricated, quasi-static and fatigue mechanical behavior of GFRP composites was characterized to be used in the FTPF model. The prediction capability of the FTPF model was tested based on the experimental data obtained for multidirectional laminates of various composite materials. Fatigue life prediction results of the glass/epoxy laminates were found to be better as compared to those for the linear fitting predictions. The results also indicated that the approach with exponential fitting provides better fatigue life predictions as compared to those obtained by linear fitting, especially for glass/epoxy laminates. Moreover, an optimization study using the proposed methodology for fatigue life advancement of the glass/epoxy laminates was performed by a powerful hybrid algorithm, PSA/GPSA. So, two optimization scenarios including various loading configurations were considered. The optimization results exhibited that the optimized stacking sequences having maximized fatigue life can be obtained in various loading cases. It was also revealed that the tension-compression loading and the loadings involving shear loads are critical for fatigue, and further improvement in fatigue life may be achieved by designing only symmetric lay-ups instead of symmetric-balanced and diversification of fiber angles to be used in the optimization.

Development and validation of a simulation methodology for composite joints with delamination arresting features

This paper presents the development of a modelling methodology in a finite element framework for the simulation of novel composite joints with delamination arresting features. The investigated composite joints employ the co-consolidation technique for the assembly of composite skins and stiffeners in a structural joint; in order to arrest and retard delamination damage evolution that may appear during service life, crack stopping features are included in the joint. Progressive damage modelling and cohesive zone modelling methodologies are employed for the analysis of intralaminar and interlaminar failure of laminate composite materials components. The modelling and simulation of experimental test cases available in the open literature are used for validation of the developed progressive damage and cohesive zone models through comparison of numerical results to respective experimental results for all test cases. The mechanical response of the butt-joint structural element is experimentally investigated and linear/nonlinear finite element models are developed to simulate its mechanical behaviour. The comparison between the experimental and numerical results demonstrates the applicability of the developed methodology in the simulation of novel composite structural joints with crack-stopping features.

Improving the damage tolerance of Si3N4 by forming laminate composites with refractory metals

The objective of this research was to demonstrate that the damage tolerance of Si3N4 could be significantly improved by forming laminate composites with refractory metals, providing materials that undergo graceful failure, rather than the fast-fracture mechanism exhibited by monolithic Si3N4. A damage tolerant Si3N4 could be used as a ring material in an all-ceramic bearing, decreasing the chance for catastrophic failure if the ring is stressed in tension during operation. The technical approach formed a laminate composite material using alternating Si3N4-metallic layers, with both outer layers being Si3N4 to take advantage of its greater wear resistance, chemical stability, and thermal stability. The metallic layers are designed to arrest any cracks in the outer layers, thus producing a toughened Si3N4 and avoiding the catastrophic failure behavior exhibited by monolithic ceramics. The laminate composites were fabricated using a combination of tape-casting Si3N4 and metals from slurries, as well as metal foils, followed by hot pressing at 1500°C. The metallic materials employed were chromium, titanium, and tantalum. Analysis confirmed that the interfaces were well formed, and the laminates with chromium and titanium formed intermetallic compounds more readily than the composites with tantalum. The Si3N4-Ta laminates demonstrated crack deflection and bridging behavior during failure and flexural strength of 800–900 MPa. The hardness and elastic modulus of Si3N4-Ta laminates measured by nanoindentation were similar to those reported in literature. The hardness across the interface of the Si3N4-Ta composite varied according to the composition of the interface, which displayed a profile indicative of a diffusion bond.

Milling Parameter Optimization of Continuous-Glass-Fiber-Reinforced-Polypropylene Laminate.

The composite-material laminate structure will inevitably encounter connection problems in use. Among them, mechanical connections are widely used in aerospace, automotive and other fields because of their high connection efficiency and reliable connection performance. Milling parameters are important for the opening quality. In this paper, continuous-glass-fiber-reinforced-polypropylene (GFRPP) laminates were chosen to investigate the effects of different cutters and process parameters on the hole quality. The delamination factor and burr area were taken as the index to characterize the opening quality. After determining the optimal milling tool, the process window was obtained according to the appearance of the milling hole. In the selected process parameter, the maximum temperature did not reach the PP melting temperature. The best hole quality was achieved when the spindle speed was 18,000 r/min and the feed speed was 1500 mm/min with the corn milling cutter.