Aluminum Laminates Research Articles

Incremental Sheet Forming of Metal-Based Composites Used in Aviation and Automotive Applications

For several years, the aviation industry has seen dynamic growth in the use of composite materials due to their low weight and high stiffness. Composites are being considered as a means of building lighter, safer, and more fuel-efficient automobiles. Composite materials are the building material of a relatively new kind of unmanned aerial vehicle, commonly known as a drone. Incremental forming methods allow materials to be quickly formed without the need to manufacture conventional metal dies. Their advantage is the high profitability during the production of prototypes and a small series of products when compared with the conventional methods of plastic forming. This article provides an overview of the incremental forming capabilities of the more commonly produced aluminium- and titanium-based laminates, which are widely used in the aircraft industry. In addition, for composites that are not currently incrementally formed, i.e., aramid-reinforced aluminium laminates, the advantages and potential for incremental forming are presented.

The effect of electrophoretic deposition of carbon nanotubes onto carbon fiber on the interlaminar resistance of carbon reinforced aluminum laminates

Functionalized multi-walled carbon nanotubes were deposited on the carbon fabric using ultrasonic-assisted electrophoretic deposition. The effect of carbon nanotubes (CNTs) deposition time and morphology on the mode I interlaminar fracture resistance of carbon reinforced aluminum laminates (CARALL) was investigated. The formation of a proper network of CNTs on the carbon fabric favorably deviated the crack growth into the carbon fabric layer and intensified the fiber bridging during the delamination. The CNT coating on the carbon fiber in conjunction with the alkaline-acid treatment on the Al substrate significantly promoted the interlaminar fracture initiation and propagation energies and stabilized the fracture behavior.

Development and shelf‐life assessment of Ready‐to‐Bake frozen potato Paranthas fortified with iron and zinc

SummaryThe present investigation was carried out to prepare iron‐ and zinc‐fortified ready‐to‐bake frozen potato paranthas that were packed in aluminium laminates and vacuum packs and stored under frozen conditions (−18°C). Paranthas were evaluated for proximate, bioactive, microbial and organoleptic parameters. In vitro bioavailability of iron was 70.24% and the zinc was 72.68% in EFP. Iron and zinc compounds in UFP and EFP remained stable throughout the storage period irrespective of their packaging material and thus improved the nutritional profile of the paranthas. Total phenols decreased from 109 mg to 105 mg and 109 mg to 107 mg/100 g in aluminium laminate and vacuum‐packed samples respectively. The shelf‐life analysis revealed that the product can be effectively stored for 3 months in aluminium laminates and 5 months in vacuum packs. Hence, to tackle malnutrition, fortified ready‐to‐bake frozen potato paranthas will be an effective technology to deliver convenience and industrial applicability.

The effect of laser-texturing configurations on the interfacial resistance of carbon reinforced aluminium laminate

ABSTRACT Laser ablation can be incorporated for surface treatment of carbon-reinforced aluminium laminate (CARALL) with environmental benefit as compared to chemical treatments. In the present research, laser surface structuring with different patterns was implemented on the aluminium substrates. The effect of laser-texturing pattern on the performance of CFRP/Al (carbon fiber reinforced polymer/aluminium) interface was investigated by undertaking lap shear, modes I and II interlaminar fracture tests. The laser surface structuring developed micro topography on the metal adherent and enhanced the interfacial area, mechanical interlocks, fiber bridging and cohesive failure in the CFRP/Al interface. The X-pattern with six successive passes of laser ablation offered the highest laser surface coverage (85.6%), leading to the improvement of lap shear strength, mode I and II critical interlaminar fracture toughness as high as 40, 110 and 52%, respectively, as compared to the chemical treated samples.

Effect of intermetallic compounds distribution on bonding strength of steel–aluminum laminates

In this study, steel–Al laminates are prepared via hot-roll bonding and annealed for various durations to generate intermetallic compounds (IMCs) with different distributions at the interface. The fracture forms of the laminates with different IMCs distributions are analyzed via in-situ tensile–shear experiments, and the shear stress distribution in the regions adjacent to the bonding interface during the tensile–shear process is investigated via finite element modeling using Abaqus. Results show that granular IMCs can change the direction of cracks and limit crack expansion during the tensile–shear process. The location of the maximum shear stress shifts from the interface to the aluminum matrix, causing fracture to be generated in the Al matrix. When an approximate IMC layer is formed at the bonding interface, the maximum shear stress occurs at the IMC–Al interface. Additionally, Kirkendall voids, which are the source of cracks, are observed at the IMCs–Al interface. They expand along the IMC–Al interface during the tensile–shear process, thus reducing the bonding strength. This study shows that granular IMCs are beneficial for improving the bonding strength, and that the bonding strength begins to deteriorate when the IMCs accumulate to form a layer.

Investigation of analytical model of crack propagation under multi axial fatigue in fiber metal laminate

Mostly the aerospace and other applications parts during their service life are subjected to the multi axial fatigue with non-proportional loading. In this study, the fatigue crack growth in glass laminate aluminum reinforced epoxy subjected to special case of non-proportional multiaxial fatigue (cyclic tension with constant shear) has been investigated. New prediction analytical model used empirical Paris equation has been adopted. Crack-growth rate was in relation with the equivalent stress-intensity factor for mixed mode at the crack-tip. Bridging stress-intensity factor was superimposed with the far-field stress-intensity factors to evaluate the equivalent stress-intensity factor. Bridging stress distribution, crack opening contour, delamination shape and its growth have been estimated simultaneously to evaluate the bridging stress-intensity factor. The obtained results indicated that there was a considerable enhancement in the crack growth rate (193.8%), number of cycles required to full failure (192%) and other performance characteristic as compared with the monolithic aluminum. Numerical simulation by ABAQUS 2021 software has been implemented to verification of the analytical model. A significant convergence in behavior between the extracted results from both analytical model and numerical simulation with maximum deviation reach to 8.2%.

FE Model for Bird Strike Simulation on ARALL Leading Edge

AbstractThis paper deals with the development of a finite element (FE) model for the simulation of a bird strike event on an innovative leading edge made of ARALL (ARamid ALuminum Laminate) material. To assess the reliability of the FE analyses, a preliminary model is developed aiming to simulate a tensile test, according to literature, involving ARALL specimens. Such model provides a good level of accuracy. So, the same modeling technique has been used for the bird strike simulation. Finally, the structural response of the ARALL leading edge has been compared against a conventional Aluminum one. Such a comparison has highlighted the capability of ARALL material in withstanding bird strike events with an improved performance.

Progressive Damage Behaviour Analysis and Comparison with 2D/3D Hashin Failure Models on Carbon Fibre-Reinforced Aluminium Laminates.

It is known that carbon fibre–reinforced aluminium laminate is the third generation of fibre metal materials. This study investigates the response of carbon fibre–reinforced aluminium laminates (CARALL) under tensile loading and three-point bending tests, which evaluate the damage initiation and propagation mechanism. The 2D Hashin and 3D Hashin VUMAT models are used to analyse and compare each composite layer for finite element modelling. A bilinear cohesive contact model is modelled for the interface failure, and the Johnson cook model describes the aluminium layer. The mechanical response and failure analysis of CARALL were evaluated using load versus deflection curves, and the scanning electron microscope was adopted. The results revealed that the failure modes of CARALL were mainly observed in the aluminium layer fracture, fibre pull-out, fracture, and matrix tensile fracture under tensile and flexural loading conditions. The 2D Hashin and 3D Hashin models were similar in predicting tensile properties, flexural properties, mechanical response before peak load points, and final failure modes. It is highlighted that the 3D Hashin model can accurately reveal the failure mechanism and failure propagation mechanism of CARALL.

Strain rate effect analysis of hybrid composites under the high-velocity impact

In this paper, the damage behavior of fiber metal laminate (FML) is studied under high-velocity impact (HVI) at different strain rates (1 s−1, 100 s−1, and 1000 s−1) for flat, hemisphere, and sharp nosed projectiles. A finite element model has been used to examine the damage modes and failure processes of carbon fiber reinforced aluminium laminates (CRALLs) under HVI. This study is based on continuum damage mechanics. The damage criteria for aluminium (Al) and carbon fiber composite layers are identified by Johnson-Cook (J-C) and Hashin damage models, respectively. To analyse the inter-laminar de-lamination caused by the HVI, a cohesive surface regulated by bi-linear traction-separation is applied. The CRALL ballistic limit is analysed for different projectiles, which strike at initial velocity ranges from 60 m/s to 150 m/s to the CRALL. The obtained numerical results are in good agreement with the literature experimental results, which indicates the model is permissible for further analysis. The obtained results show that if strain rate varies from 1 s−1 to 1000 s−1 then CRALL ballistic limit velocity increases for all projectiles. The CRALL ballistic limit is the highest for flat nosed projectiles, followed by hemisphere and sharp nosed projectiles.

Experimental investigation of Glass Laminate Aluminium Reinforced Epoxy characteristics influences through low velocity impact test

ABSTRACT The fibre being one of the recently implemented advanced materials in distinctive applications is being reinforced with metals to constitute a unique composite laminate. This reinforcement will enhance the sustenance property of the laminate used in automotive sectors. In most automotive sectors, drop weight analysis at varying velocity ranges is performed to evaluate the damage characteristics of the vehicle body. Hence, the present work leads us through the study on influence of low-velocity impact at varying heights over the Glass Laminate Aluminium-Reinforced Epoxy (GLARE) laminate characteristics. Here, the laminate of constant thickness was subjected to drop weight impact. Three distinct thicknesses of (0.2, 0.3 and 0.4 mm) Al-2024 T3 aluminium alloy were used. The results indicate that laminate can sustain up to critical load in terms of impact velocity as 3.13 m/s, and beyond which, it leads to delamination damage at 3.49 m/s. The above results indicate that the maximum absorbed energy by the laminate before catastrophic failure (crack) was noticed to be 14.43 J in the case of sample B. Further, it is noticed that GLARE laminate with 0.3 mm face sheet thickness has best results with reference to both absorbed energy and damage when compared with other thicknesses.

RECYCLED PLASTIC COMPOSITES IMPREGNATED WITH ORGANOCLAY AS POTENTIAL GEOGRID REINFORCEMENT MATERIAL FOR PAVEMENT APPLICATION

Geogrid in pavement application is widely used today, as it mainly functions as soil reinforcement or as a separator. Geogrid is made up of polymers which makes it resistant to degradation. There are different kinds of polymers which are widely used today in a familiar term called plastics. For the past years, plastic aluminum laminates (PAL) and high-density polyethylene (HDPE) plastic bags were used as packaging materials or containers. However, the use of these plastics generates a huge amount of waste, consuming a lot of space and damaging the natural state of the earth. This research aims to utilize these wastes to form geogrid, which will be applied in pavement design. The recycled plastics undergo the melting process, with the aid of the two-roll mill and the compression molding. Then apertures are carved into a grid-like structure. A total of nine mixtures of geogrids were produced, each mixture having a different composition of HDPE, PAL, and organoclay. Tensile test for geogrids by Multi-rib Tensile Method (ASTM 6637) and tensile test for plastics (ASTM D638) are followed to test the geogrids. Based on the data obtained, it showed that higher tensile strength is achieved when the amount of HDPE composition in the material increases. In terms of the addition of organoclay, the mixture with 98% HDPE and 2% organoclay produced the highest tensile strength. The product of the study exhibiting the highest strength was classified as either class 2 or class 3 geogrid.

Green Corrosion Inhibition on Carbon-Fibre-Reinforced Aluminium Laminate in NaCl Using Aerva Lanata Flower Extract.

Aluminium-based fibre–metal laminates are lucrative candidates for aerospace manufacturers since they are lightweight and high-strength materials. The flower extract of aerva lanata was studied in order to prevent the effect of corrosion on the aluminium-based fibre–metal laminates (FMLs) in basic media. It is considered an eco-friendly corrosion inhibitor using natural sources. Its flower species belong to the Amaranthaceae family. The results of the Fourier-transform infrared spectroscopy (FTIR) show that this flower extract includes organic compounds such as aromatic links, heteroatoms, and oxygen, which can be used as an organic corrosion inhibitor in an acidic environment. The effectiveness of the aerva-lanata flower behaviour in acting as an inhibitor of the corrosion process of FMLs was studied in 3.5% NaCl solution. The inhibition efficiency was calculated within a range of concentration of the inhibitor at room temperature, using the weight-loss method, potentiodynamic polarization measurements and electrochemical-impedance spectroscopy (EIS). The results indicate a characterization of about 87.02% in the presence of 600 ppm of inhibitor. The Tafel curve in the polarization experiments shows an inhibition efficiency of 88%. The inhibition mechanism was the absorption on the FML surface, and its absorption was observed with the aid of the Langmuir adsorption isotherm. This complex protective film occupies a larger surface area on the surface of the FML. Hence, by restricting the surface of the metallic layer from the corrosive medium, the charge and ion switch at the FML surface is reduced, thereby increasing the corrosion resistance.

Impact resistant basalt fiber-reinforced aluminum laminate with Janus helical structures inspired by lobster and mantis shrimp

Fiber metal laminate (FML) is an extremely strong and light material that is widely applied in the structural components of aircraft for weight reduction and improving mechanical properties. However, the effective integration of excellent structural failure tolerance property and superior stress dissipation capacity into one FML material remains a huge challenge. Herein, inspired by the non-linear helical structure of lobster and the linear helical structure of mantis shrimp, a novel bioinspired FML with Janus helical structure was designed and manufactured through the method of hot press forming. Afterwards, low velocity impact tests were carried out to evaluate the impact resistant property. Remarkably, the peak impact force of the bioinspired Janus FML (BJFML) at the impact energy of 40 J was 8216.36 N, which increased by 10.22% compared with the 7454.52 N of traditional cross-ply FML (CPFML). Moreover, the dent depth of the BJFML (5.95 mm) decreased by 28.23% compared with that of CPFML (8.29 mm). Finally, the finite element simulation was conducted systematically. In fact, the non-linear helical arrangement greatly hindered crack propagation and the periodic linear structure improved its load homogenizing ability for impact forces, thus improving structural failure tolerance, strengthening stress dissipation, and synergistically enhancing the impact resistance.

An Approach to Improving Formability of Exterior Package for Lithium Ion Secondary Battery with Forming Die for Aluminum Laminate

An Approach to Improving Formability of Exterior Package for Lithium Ion Secondary Battery with Forming Die for Aluminum Laminate

Experimental and statistical evaluation of wear and friction behaviour on AA 7475/GFRP multi-stacked fibre metal laminates

Fibre metal laminates (FMLs) are used to make lugs and cargo doors in the aviation industry. In both the assembly and service of aircraft, friction and wear are unavoidable. This paper explores the experimental and statistical evaluation of wear and friction response of multi-stacked glass laminate aluminum reinforced epoxy (GLARE) under dry sliding conditions. Testing was conducted by a pin on disc machine with four parameters namely specimen condition, contact pressure, sliding velocity, and sliding distance. Material heterogeneity is a factor that is supposed to improve the damping of the hybrid system. The design of experiment (DOE) reveals that specimen condition significantly promotes wear and friction. On the other hand, sliding velocity did not effectively contribute to loading the hybrid towards the dry slide. The best specimen condition for wear was C2, with contact pressure of 50 MPa, sliding velocity of 1 m/s, and sliding distance of 3000 m. For friction, best specimen condition C3, with contact pressure 100 MPa, sliding velocity 1 m/s, and sliding distance 1000 m. Scanning electron microscopy was also used to investigate the wear mechanisms on the worn surface. A linear regression model shows a 98% correlation of experimental with predicted values.

Investigation on graphene addition on the quasi-static and dynamic responses of carbon fibre-reinforced metal laminates

In this paper, graphene nanoplatelets (GnPs) were used with carbon fibre/epoxy composite to enhance the mechanical performance of fibre metal laminates (FMLs). The designed FMLs are composed of thin aluminium alloy layers alternating with carbon-fibre epoxy/GnP composite plies with a chemical treatment performed on the aluminium laminate to promote adhesion strength with the epoxy composite. Two different configurations of FMLs were investigated (i) composite plies with unidirectional carbon fibres (U-FMLs) and (ii) composite plies with plain carbon woven (W-FMLs). Samples were tested under dynamic loading (Charpy impact) and quasi-static loading (three-point flexure). The experimental results showed that FMLs with 0.3 wt% GnPs logged the best impact performance; the impact strength of W-FMLs and U-FMLs are respectively 18.2% and 25.2% higher than FMLs without GnPs. FMLs with 0.5 wt% GnPs recorded the highest enhancement in flexural strength, fracture strain and flexural modulus recording increments 23.1%, 19.3% and 48% for the W-FMLs, and 60.3%, 34.5% and 61.4% for the U-FMLs, respectively. Also, an in-depth microscopic analysis was conducted to understand the reinforcing mechanism of GnPs into FMLs. Moreover, a numerical model of a three-point flexural test was developed to show the ability of numerical tools to predict material behaviour at optimized costs. Johnson–Cook and Hashin damage models were used respectively for aluminium alloy and carbon fibre epoxy/GnP composite to accurately predict their deformation and damage modes.

Damage to inverse hybrid laminate structures: an analysis of shear strength test

Abstract Hybrid laminates with continuous fiber reinforcement, such as glass reinforced aluminium laminate (GLARE), aramid reinforced aluminum laminate (ARALL), or carbon reinforced aluminum laminate (CARALL), have been developed to increase the lightweight potential and fatigue resistance applied for aircraft structures. However, the use of thermosetting matrices imposes material limitations regarding recycling, malleability, and manufacturing-cycle times. The inverse hybrid laminate approach is based on a continuous fiber-reinforced thermoplastic matrix, in which a metal insert is integrated. For efficient manufacturing of the novel composites in high-volume production processes, conventional sheet metal–forming methods have been applied. It helped to reduce the cycle times and the costs of the forming equipment compared to currently used hybrid laminate-processing technologies. The present study analyzes the damage to the inverse hybrid laminate structures resulting from the interlaminar shear strength test. The tests were performed for eight laminate material configurations, which differed by the type and directions of the reinforced glass and carbon fibers in the polyamide matrix and the number of the fiber-reinforced polymer (FRP) layers in the laminates. Industrial computed tomography and scanning electron microscopy were used for analysis. Observed damages, including fiber–matrix debonding, fiber breakages, matrix fractures, interfacial debonding, and delamination in selected areas of the material, are strictly dependent on the laminate configurations. FRP layers reinforced by fibers perpendicular to the bending axis presented better resistance against fractures of the matrix, but their adhesion to the aluminum inserts was lower than in layers reinforced by fibers parallel to the bending axis.

Damping contribution of the glass reinforced aluminum laminates epoxy to the aluminum based-sandwich structures

Despite many potential use of aluminum sandwiches in advanced industries, their poor performance in damping and sound transmission demands new challenges for improvement. This study aims to improve dynamic performance of these sandwiches using hybrid face sheets in the form of Glass Laminate Aluminum Reinforced Epoxy (GLARE). While parameters related to the aluminum honeycomb core were kept constant, the effects of different fiber orientations of the GLARE on the fundamental natural frequency, equivalent flexural modulus, and especially damping values were investigated. The dynamic values of the structures have been measured using a specially designed non-contact vibrating beam test with free-free end conditions. A comparison of the sandwiches with the GLARE and with bare aluminum face sheets has also been made to find out their differences in the dynamic performance. The experimental results were compared to those from a numerical modal analysis via the Altair Hyperworks 2019 Software. The results have shown that the maximum equivalent modulus is obtained from the specimen with the unidirectional (0°) fibers, and the minimum value is from that with the 90° ones. But the opposite is the case if their Specific Damping Capacity values are compared. The values of the specimens with 0°/90° and 0°/45° fibers are on moderate levels. Considerable increments between 54% and 172% are found in the damping values of the specimens with GLAREs, compared to those with the bare aluminum face sheets. The results from the experimental and numerical works have been found in a good agreement.

Dynamic response of sandwich plates with GLARE face-sheets and honeycomb core under metal foam projectile impact: Experimental and numerical investigations

Aluminum honeycomb sandwich plate with fiber metal laminate (FML) as panel can combine the advantages of FML face-sheet and honeycomb core, and has advantages of high specific strength / specific stiffness, lightweight and good energy absorption performance. In this paper, the dynamic response of aluminum honeycomb sandwich plates with Glass Laminate Aluminum Reinforced Epoxy (GLARE) face-sheets under metal foam projectile impact is studied. The single foam projectile impact test is conducted to study the dynamic response of honeycomb sandwich plates with GLARE face-sheets. The debonding between metal and composite layers of the front face-sheet, the fiber fracture, buckling, shear and fracture of core are observed. Also, the multiple foam projectile impact test is carried out to study the impact resistance of the sandwich plate. The numerical calculation is conducted, numerical results are compared with experimental ones. Influences of the impulse, face-sheet thickness, fiber laying angle, honeycomb height, wall thickness of core and cell length of honeycomb on impact resistance and energy absorption of sandwich plates are discussed. It is found that the improvement range of the maximum deflection of back face-sheet gradually decreases with the increase of face-sheet thickness. In addition, by increasing the impulse, decreasing the face-sheet thickness and decreasing the core stiffness, the energy absorption of sandwich plates under metal foam projectile impact can be enhanced. These findings can be used to guide the optimal design of FML sandwich structures under metal foam projectile impact.

Impact Properties of Novel Natural Fibre Metal Laminated Composite Materials

Fibre metal laminates (FMLs) are lightweight structures with high structural performance and are suitable for many industrial applications. This work describes the impact behaviour of novel sisal fibre-reinforced aluminium laminates (SiRAL) and their dependence upon the orientations of the fibres, the composite core used and the surface treatment of the metal skins. A cold-pressing technique is used to produce SiRALs in six configurations. The FMLs here also have treated or untreated aluminium skins (2024 T3) and three different types of core materials (0°/90° fabric, ±45° fabric and random matt). The ±45° core treated SiRAL provides the highest energy absorption and deflection properties. The pre-treatment of aluminium skins using sandpaper, deep cleaning and primer significantly affects the delamination of the panels under bending impact. The findings reveal that the SiRAL concept is a promising multifunctional FML suitable for different applications that require lightweight, bending and impact performance, together with sustainability characteristics.