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In earthquakes, foundations of structures may encounter damages due to faulting. To address this issue, numerous innovative mitigation methods have been introduced. Among these, an efficient solution involves constructing a trench wall filled with a material capable of not only absorbing the faulting energy but also diverting the propagation route of fault rupture. In this research, a novel material called closed-cell aluminum foam (CCAF) is introduced to be implemented within the trench wall considering its noticeable energy absorbing and flexibility. To evaluate the performance of the trench wall filled with CCAF [or Aluminum Foam Wall (AFW)] under fault rupture conditions, ABAQUS, a Finite Element Method software, is employed for numerical analyses and the obtained results are validated against centrifuge experimental data for both free field and shallow foundation's presence conditions. Based on the findings, the application of AFW resulted in a substantial reduction in the rotation degree of the shallow foundation. In one case, it experienced a significant decrease from 11.64° to a mere 0.48°. Furthermore, when compared to alternative mitigation methods such as Smart Wall Barrier (SWB) or Soil Bentonite Wall (SBW), AFW exhibited superior performance under identical conditions. In similar conditions, AFW achieved a remarkable rotation degree of 0.06°, while SWB and SBW registered rotation degrees of 0.4° and 0.2°, respectively. The obtained results indicate that AFW demonstrates a promising ability to efficiently absorb faulting energy and divert the propagation of fault rupture. [ABSTRACT FROM AUTHOR]

Aluminum foam sandwich (AFS) are widely used in energy absorption because of their light weight and excellent energy dissipation capabilities. In this study, energy absorption, deformation modes, and dynamic response of AFS under low-velocity impact are investigated using experimental and numerical approaches. Dynamic impact tests are performed utilizing a drop hammer impact test on AFS with different core densities, face sheet thicknesses, and impact energy. Based on the 3D Voronoi foam model, a full-scale finite element model (FEM) is developed to simulate the mechanical response of AFS under low-velocity impact, and verified by experimental results. The contributions of different AFS components to energy absorption at various impact velocities are further analyzed, along with the effects of face sheet thickness distribution. The results indicate that the performance of the face sheet and core and the impact energy have a remarkable influence on the low-velocity impact response and damage modes of the AFS. The type of structure configuration, "thin top and thick bottom," enables the AFS better play its energy absorption while ensuring the overall light weight. This study provides a reference for the design and optimization of the face sheet thickness of AFS when it is used as an energy-absorbing member and improves their design efficiency. [ABSTRACT FROM AUTHOR]

Nowadays, hybrid structures, which combine low‐density composites with low‐cost thin‐walled metals, have shown great effect in enhancing the performance of automotive body structures, especially the energy absorber components. This study focuses on the experimental and numerical investigation of the bending energy absorption behavior of CFRP/aluminum hybrid double hat‐section beams used in the side part of the car body. In the experimental section, two types of double hat‐section beams were fabricated: aluminum and Al/CFRP. These beams were then subjected to quasi‐static three‐point bending tests. The results demonstrated that the hybrid beam exhibited superior energy absorption capabilities compared to the single beam. Subsequently, a finite element model was developed using LS‐Dyna software and was validated by comparing the experimental and numerical load–displacement results. In‐depth numerical analyses were conducted to investigate the influence of various design parameters, including CFRP‐reinforcement configuration, numbers of CFRP layers, CFRP ply‐angle, CFRP reinforced length, and aluminum/CFRP mass, on crashworthiness indicators. The numerical findings indicate that the hybrid beam with 04, 45/−45s ply‐angles exhibited better crash force efficiency (CFE) and specific energy absorption (SEA) compared to other ply‐angles, respectively. Furthermore, increasing the number of CFRP layers within the total beam's mass improved its energy absorption capacity. It was also revealed that the CFRP length on the upper and lower hats could be considered as 42.5% of the total aluminum beam length, as opposed to the full CFRP length, providing enhanced energy absorption capabilities. Highlights: Bending behavior of the Al and Al/CFRP double hat section beams.Effects of variable thickness and identical mass on the double hat section beam.Effects of variable ply angle and number of CFRP layers on the hybrid beams.Discrete effect of CFRP reinforcement configurations and inner CFRP lengths. [ABSTRACT FROM AUTHOR]

This study examines the nonlinear dynamic response of sandwich plates under low-velocity impacts (LVIs), which consist of a porous aluminum foam core with functionally graded (FG) graphene platelets (GPLs) reinforcement and two titanium alloy face sheets. The finite element method is employed to perform the numerical simulations and the Hertz contact theory is used to model the impact behavior. The generic Halpin-Tsai model, which incorporates the porosity effect, is adopted to estimate the mechanical properties of core made of the FG-GPLRC, based on the experimental data of the closed-cell aluminum alloy foam. The simulation results reveal that the FG-X configuration has the highest impact resistance, and that the addition of GPLs improves the impact performance. Moreover, a thicker core can reduce both the first contact time and the vibration period of plates, while a looser boundary condition can prolong the vibration time after the first impact. Additionally, a higher impactor velocity, mass and radius lead to a higher deflection and contact force. The oblique impact decreases the impact energy. This work provides a lighter and stiffer design for structure engineers when components suffer low-velocity impact. [ABSTRACT FROM AUTHOR]

The construction of lithium–sulfur battery cathode materials while simultaneously achieving high areal sulfur‐loading, adequate sulfur utilization, efficient polysulfides inhibition, rapid ion diffusion, etc. remains a major challenge. Herein, an internal regulatory strategy to fabricate the unique walnut‐like yolk–shell carbon flower@carbon nanospheres is presented (WSYCS) as sulfur hosts. The internal carbon flower, suitable cavity, and external carbon layer effectively disperse the insulate sulfur, accommodate volumetric expansion, and confine polysulfides, thus improving the performance of lithium–sulfur batteries. The finite element simulation method also deduces the enhanced Li+ diffusion and lithium–sulfur reaction kinetics. More importantly, WSYCS2 is grafted onto carbon fiber (CF) by electro‐spinning method to form a tandem WSYCS2@CF 3D film as a sulfur host for the free‐standing electrode. The corresponding battery exhibits an extremely high areal capacity of 15.5 mAh cm−2 with a sulfur loading of 13.4 mg cm−2. Particularly, the flexible lithium–sulfur pouch cell delivers a high capacity of 8.1 mAh cm−2 and excellent capacity retention of 65% over 800 cycles at a relatively high rate of 1C, corresponding to a calculated energy density of 539 Wh kg−1 and 591 Wh L−1. This work not only provides guidance for tailoring thick carbon/sulfur electrodes but also boosts the development of practical lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

In this study, adhesive bonding of aluminum (Al) to glass fiber reinforced polymer (GFRP) was investigated using finite element analysis to optimize bond strength. Mechanical surface preparation has a great influence on the chemical properties (increasing surface energy and creating a stronger bond) and mechanical properties (creating mechanical interlocking and increasing friction) of adhesive bonding. Hence, the response surface method was employed to examine the influence of groove number (1, 3, 5), groove angle (0, 45, 90°), groove shape (V-shape, square, concave), and joint type (metal–metal, metal–composite, composite–composite) on the tensile strength of the bond. To simulate the bond behavior of Al/GFRP under different parameter conditions, the cohesive zone model was used to consider the crack growth. Optimization results obtained by the desirability function method showed that the maximum bond strength was achieved with a groove number of 1, groove shape of square, groove angle of 0°, and metal–metal joint type. The optimization results predicted by the desirability function and finite element analysis were in good agreement with those obtained by experimental tests. [ABSTRACT FROM AUTHOR]

AbstractThree-dimensional Voronoi models are built to analyze the buffering and energy absorption performance of stepwise density-graded aluminum foams during quasi-static and dynamic compression. The validity of the aluminum foam model with selected mesostructure and simulation parameters is verified by the correlation between the experimental and numerical results. Strain-stress responses, deformation propagation, and energy absorption capabilities are compared and analyzed to probe the deformation mechanisms and stress transmission. The results show that there are three deformation modes: quasi-static mode, transitional mode, and dynamic mode, which are formed successively with increasing compression velocity. The method of obtaining the first critical velocity of the deformation mode transformation in two-dimensional stepwise density-graded aluminum foams is extended to the three-dimensional cases. Meanwhile, a new method based on the deformation concentration is developed to determine the second critical velocity. The different stepwise density graded aluminum foams exhibit similar performances under quasi-static mode, but exhibited significant differences under dynamic mode. However, a negative gradient of aluminum foam is advantageous for reducing the stress on the support end and optimizing the energy absorption under dynamic mode. [ABSTRACT FROM AUTHOR]

Deviation from the nominal dimension in the sense of component distortion is a quality‐reducing phenomenon in the foundry. This distortion problem as a result of impeded solidification and cooling shrinkage is of particular importance for permanent mold casting with its mechanically stiff and thermally well‐conducting molds. In studies, the temperature when the mold constraint is removed has already been identified as one of the dominant factors influencing the dimensional deviations of the casting. So far, however, no clear dependencies have been described. In the present work, the temperature up to the removal of the mold constraint is varied from near solidus to ambient temperature on a specially designed permanent mold casting made of AlSi7Mg0.3. This is compared with thermally and mechanically coupled finite elements method calculations of the investigated test geometry and the resulting component distortions. Finally, the applicability of the distortion prediction for the development of compensation strategies is evaluated. [ABSTRACT FROM AUTHOR]

Cylindrical specimens are of great interest in analyzing mechanical elements' behavior and investigating phenomena with biaxial loads. It is necessary to identify the behavior of the crack front along the thickness to interpret these results, which are usually based on the hypothesis of a straight crack and the observation of the outer face of the crack front. Based on the work carried out on compact tension type specimens, this work proposes adapting this methodology to cylindrical specimens, adapting the previous finite element models. Cylindrical specimens provide an asymmetric behavior influenced by the radius, where the CT (compact tensile) specimen can be considered the extreme infinite radius case. Combinations of the load level and radius values help us simulate the crack's behavior under intermediate hypotheses between a plane crack theory and a three-dimensional one. The plastic strain around the crack front will be analyzed as a function of the thickness and the load level applied. The results allow us to validate the numerical methodology and establish the differentiated behaviors of the plastic zones close to the outer and inner radii. [ABSTRACT FROM AUTHOR]

This work aims to research the oblique lateral crushing behavior of CFRP/AL hybrid tubes under different parameter configurations. First, a finite element model was established based on the maximum stress criterion and the traction‐separation law. The reliability of the numerical models for pure aluminum, pure composite, and hybrid tubes was verified by rigorous comparison with experimental data, respectively. Second, the influence of loading conditions and geometric characteristics on crashworthiness were studied. The results show that the damage modes of the hybrid tube under oblique lateral loading are mainly concentrated in the horizontal and vertical ends, specifically in the form of plastic hinge and fiber, matrix fracture. The CFRP layers has positive effect on improving the specific energy absorption (SEA). High ratio thickness of aluminum tubes can effectively improve the energy absorption (EA) and crush force efficiency (CFE). It is found that the sandwich structure is not conducive to resist lateral crushing, while the CFRP without external constraints can absorb more impact energy. Highlights: The oblique lateral crushing behavior of CFRP/AL hybrid tube was studied.A numerical simulation method was proposed and verified.The effects of loading angle, fiber layers and AL thickness were studied.The hybrid ratio and hybrid method were designed and discussed. [ABSTRACT FROM AUTHOR]

The effects of structural parameters on the forming quality and mechanical properties of CFRP (carbon fiber reinforced polymer)/Al (aluminum) self-piercing riveting (SPR) were investigated and optimized by combining experiment and numerical simulation. Firstly, the SPR 3D finite element model (FEM) was established, in which a continuous damage model (CDM) based on the strain-determined Hashin failure criterion was established to simulate the intra-layer damage of CFRP, and the inter-layer damage was simulated by using cohesive behavior. Subsequently, the effects of rivet length, die diameter, die depth, sheet thickness and width, rivet end distance, and CFRP layup sequence on the SPR cross-sectional dimensions (interlock, bottom remaining thickness) and shear results (peak shear load, energy absorption) were systematically investigated based on the established FEM. Finally, a multi-objective optimization of the structural parameter combinations was performed using Grey relational analysis (GRA) combined with entropy weight method. The results showed that the interlock increased with the increase of rivet length and die diameter, and decreased with the increase of die depth and sheet thickness. The peak shear load increased with the increase of sheet width and rivet end distance. The peak shear load of the joint with [0°/90°]3 s was the largest and the energy absorption of the joint with complex layups was the largest. Normally, the peak shear load and energy absorption were proportional to the interlock. The final optimized combination of joint parameters achieved significant improvement in each indicator compared with the original FEM. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the increasing requirements of automotive lightweighting, metal/CFRP laminates are increasingly used. In this paper, Al/CFRP laminates were prepared using an integrated hot press curing method, and the optimum curing conditions were determined using the single-lap shear test at 130 °C for 45 min. The effects of fiber lay-up, forming speed, and metal layer thickness on bending springback were investigated using the V-shaped bending test and Abaqus finite element analysis method. The results show that fiber lay-up has an important influence on springback. Among the five different fiber lay-ups (0° unidirectional, 90° unidirectional, 0° orthotropic, 90° orthotropic, and 45° orthotropic), the 45° orthotropic lay-up had the lowest springback rate of 1.11%. Increasing the thickness of the sheet metal can significantly reduce the resilience rate. As the sheet thickness increased from 2 mm to 3 mm, the springback of the 90° unidirectional lay-up decreased by 43%. Springback was not sensitive to forming speed, and the difference in springback was within 1% at different forming speeds. The damage behavior of the forming process was analyzed using the three-dimensional Hashin damage law with the Vumat subroutine and microscopic analysis. Fiber and resin damage under 45° orthotropic lay-up conditions was relatively small compared to fiber damage under 0° unidirectional lay-up and resin damage under 90° unidirectional lay-up. [ABSTRACT FROM AUTHOR]

A "rigid and flexible" fiber-wrapped metal bionic hybrid structure (BH) is proposed, in which the fiber-reinforced composite is wrapped to make up for the "rigidity" of the material, and the gradient design plays the "flexibility" of the structure. Firstly, the CFRP enhanced stiffness is used as an induced mechanism to achieve variable stiffness design, which can avoid the complex processing problems faced by conventional design and effectively reduce the mass of the structure. Secondly, the crashworthiness of the Bionic Hybrid Thin-walled (BH) tube under axial and oblique loading angles was systematically investigated by changing the thickness parameter of the inner core Al to the outer CFRP winding angle using the validated finite element model. Finally, the prediction accuracy of three proxy models (RSM, KRG, SVR) is compared, and two optimization algorithms (NSGA-II and MOPSO) are combined to achieve the optimal crashworthiness under multi-angle loading conditions. The optimized BH tube has obvious advantages, most notably, the SEA is improved by 47.46%, 42.72% and 53.73% under axial collapse load compared with pure Al tube, pure CFRP tube and original BH tube, respectively. The results reported in this article provide valuable guidance on the design of new variable stiffness tubes. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the axial compression performance of concrete-filled circular-end aluminum tube (RECFAT) columns, utilizing four specimens with varying parameters such as cross-sectional aspect ratio and cross-sectional aluminum content. Axial compression tests and ABAQUS finite element extended parameter analyses were conducted, with key mechanical performance indicators such as specimen failure morphology, ultimate bearing capacity, load–displacement curve, and load–strain curve being obtained. The influence of various variation parameters on the axial compression performance of the specimen was analyzed. The results indicated that the majority of specimens underwent oblique shear failure due to local bulging of the aluminum tube plane, while specimens with an aspect ratio of 4.0 experienced overall instability failure. As the aspect ratio increased, the bearing capacity improvement coefficient and ductility coefficient of the specimen decreased and the initial stiffness of the specimen gradually decreased. As the aluminum content increased, the initial stiffness decreased, with the critical aspect ratio for overall instability being between 2.0 and 2.5. The optimal aluminum content was recommended to be between 8.5% and 13.5%. When the aspect ratio was around 2.0, the lateral strain of the round-ended aluminum tube developed faster and the constraint effect was the best. The finite element model accurately reproduced the oblique shear bulging of the round-ended aluminum tube and the internal concrete V-shaped collapse, with the axial load–displacement curve being in good agreement. Improving the strength of aluminum alloy was more conducive to improving the axial compression bearing capacity of RECFAT than increasing the strength of concrete. A simplified model and calculation method for RECFAT was proposed, with an error of less than 1%. [ABSTRACT FROM AUTHOR]

Numerical parametric study is performed to investigate ballistic impact performance of a novel fiber metal laminate (FML) based on ultra-high molecular weight polyethylene (UHMWPE) fiber composite and aluminum 2024-T3 layers. A finite element modeling is developed and validated with experimental tests. A user-defined material subroutine based on continuum damage mechanics is used to define damage constitutive model of UHMWPE composite. High velocity impact simulations shows similar modes of failure to that observed in experiments. The effect of various parameters such as metal thickness, composite core thickness, metal volume fraction (MVF), and lay-up sequence on ballistic limit velocity, absorbed energy and specific perforation energy (SPE) of samples has been investigated. The results show that increasing the number of composite layers increases the SPE while increasing the thickness of metal layers decreases the SPE. Although, as the core thickness increases, the growth of SPE decreases. Changes in the lay-up sequence do not have much effect on ballistic velocity and absorbed energy. Whereas, the MVF is an important parameter in the high velocity impact performance of the PERALL specimens. In addition, with equal MVF, stacking sequence change has no significant effect on the ballistic limit velocity. Finally, a simple linear equation is suggested to describe the relationship between MVF and specific perforation energy. [ABSTRACT FROM AUTHOR]

The variable thickness hybrid square (VTHS) tubes are used to improve the energy absorption under oblique loading and the relative advantages compared with the uniform thickness hybrid square (UTHS) tubes are studied. First, a oblique compression test and finite element model were established to analyze the deformation mode and load-displacement curve of VTHS tube. Then, the parameter studies of VTHS and UTHS tubes were carried out. The results show that increasing thickness leads the structures to be prone to global bending mode, and the energy absorption performance is reduced. Compared with UTHS, VTHS tubes can increase the specific energy absorption when the progressive crushing mode occurred at the same loading angle. Meanwhile, the progressive crushing deformation with excellent energy absorption performance can still appear when the loading angle exceeds 30°. Finally, a unified equation for the relationship between the dimensionless mean crushing force and the loading angle was proposed. [ABSTRACT FROM AUTHOR]

Ultrathick aluminum honeycomb sandwich panels, which have high strength/stiffness-to-weight ratio, have been applied widely in satellites and other aerospace fields. However, the ultrathick aluminum honeycomb sandwich panels are difficult to be machined. In many cases, laser ablation is used for the microdrilling demand of aluminum honeycomb sandwich panels. The heat flux density is the key factor during laser machining, and the microdrilling parameters, including defocusing amount and incident angle, can lead to the change of the temperature fields of upper panel, cell walls, and lower panel. To study the microdrilling process quantitatively, the finite element model (FEM) is performed to evaluate the temperature evolution of aluminum honeycomb sandwich panels during continuous laser irradiation. Moreover, continuous laser microdrilling characteristics of upper panel, cell walls and lower panel are discussed via numerical simulation. The relative errors with respect to experimental results are in range of 8% showing that simulation results of laser microdrilling are reasonable. Thus, the mechanism of laser microdrilling revealed in this study can be significant for improving the processing quality of aluminum honeycomb sandwich panels. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to investigate the performance of disks that can be increased by functionally grading the disk in the radial direction; there are several but distinct categories of literature that pertain to the fabrication of disk in the thickness direction, but to the best of the authors' knowledge, no study has been conducted yet, in which gradient composition changes radially. Design/methodology/approach: A powder metallurgy technique was used for the fabrication of Al-SiC-based, three-and five-layered functionally graded (FG) disk. The variation of volume fraction of reinforcement particles (SiC) in a disk changes radially. Finite element analysis has been performed to investigate stress distribution in a layered disk. Findings: The microstructural investigation was carried out under an optical microscope and scanning electron microscopy integrated with EDS, confirming a uniform distribution of SiC in the matrix (Al). Interface microstructure indicates a successful fabrication of FG material because the transition is uniform in the graded layer without any development of crack or void at the interface. The grain size in the layers decreases with the addition of SiC particles. Additionally, the disk hardness increases as the SiC composition in the layer increases. Practical implications: An FG disk can be used in a wide range of machinery, from power transmission assemblies to energy storage devices (e.g. flywheel, gears, rotors and disk brake). Originality/value: The proposed powder metallurgy technique could be used in industries for the fabrication of simple to complicated geometries with FG properties. [ABSTRACT FROM AUTHOR]

Cellular materials, such as aluminum foams, have proven to be excellent energy absorbents. They can be used as crushable core in sacrificial cladding (SC) for blast load mitigation. In this study, the blast absorption capacity of a brittle mineral foam-based SC is investigated through finite element modeling using the LS-DYNA software. The experimental set-up used consists of a rigid steel frame with a square cavity of 300 mm x 300 mm in the center The structure to be protected is simulated by a thin aluminum plate clamped into the rigid steel frame. The blast load is generated by 20 g of C4 high explosive set at a distance of 250 mm from the center of the plate. The blast absorption capacity of the considered SC is evaluated by comparing the maximum out-of-plane displacement of the center of the plate with and without the protective brittle mineral foam. The presence of the brittle mineral foam reduces the maximum out-of-plane displacement of the center of the plate at least by a factor of two. The brittle mineral foam is modeled both in solid elements and smoothed-particle hydrodynamics (SPH) by using Fu Chang's constitutive material law based exclusively on the results of quasi-static compression tests of the foam and a phenomenological relationship between stress, strain and strain rate. The SPH model predicts the maximum out-of-plane displacement of the center of the aluminum plate with an average relative error of 5% with respect to the experimental values. [ABSTRACT FROM AUTHOR]

Although much technological advancement has been implemented in the aluminum extrusion industry, there are still considerable expenses as tests of different process parameters or new die geometries are carried out. To reduce the amount of trial-and-error testing, it is important to understand the process variation as each parameter or piece of equipment changes. Therefore, this work performed and analyzed the numerical simulation of aluminum extrusion using the finite element method through the COMSOL® Multiphysics software. A visco-plastic modeling approach was used, where the solid, aluminum, is treated as a high viscosity fluid. Furthermore, in order to optimize the process parameters and understand the physical behavior of the problem, a metamodel was built using a quadratic response surface model and, from this, a mono and multiobjective optimization was performed using the Lichtenberg algorithm metaheuristic. The multiobjective optimization with the metamodel resulted in errors of 0 to 2% in relation to the actual response. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the acoustic noise reduction of aluminum honeycomb/carbon face sheet sandwich panel with Melamine Foam (MF) lining of variable thicknesses (25 mm & 50 mm) is numerically estimated and then experimentally verified using impedance tube based on transfer matrix method. The presence of carbon face sheets and MF lining can have a significant impact on the Transmission Loss (TL). The impedance tube can measure the TL for frequency range of 64 Hz–6.2 kHz. A conventional, two-microphone impedance tube, is connected to a sample holder downstream of the first microphone pair and a section downstream of the sample holder that accommodates a second pair of microphones. The Finite Element Analysis and experimental results are compared and found in good agreements. The TL levels for each layer of material is estimated prior to have TL for combined structure. Furthermore, the optimized insulation foam thickness of 50 mm is obtained based on required acoustic parameters. [ABSTRACT FROM AUTHOR]

Auxetic metamaterials possess superior properties and have drawn extensive attention in the past decades. Herein, two curved ribs are added to the conventional re‐entrant (CRE) honeycomb structure to form a modified auxetic re‐entrant (MRE) honeycomb structure for improving the energy absorption capacity of the structure. In‐plane quasi‐static compression response of the honeycomb in large deformation is numerically explored first. Then, quasi‐static compression test is conducted to verify the validity of the numerical simulation. Both experimental and numerical simulation results reveal that during the quasi‐static compression process, two plateau stresses occur in the load–displacement curves of the structure, and the second plateau stress is much higher than the first one. The occurrence time of the second plateau stress can be controlled by the distance between the concave curved ribs in the structure. The experimental results are in good agreement with the finite element analysis results. Due to their desirable mechanical properties, the MRE honeycomb structures have great potential for applications in civil engineering, vehicle crashworthiness, and protective infrastructure. [ABSTRACT FROM AUTHOR]

This study investigates the crashworthiness behavior of square aluminum thin-walled tubes subjected to both axial and oblique impact loading, emphasizing the effects of crushing angle and initial contact between impactor and tube on the plastic collapse initiation and energy absorption capacity. A parametric study in crushing angle is conducted until 15°, while the two examined types of initial contact between impactor and tube consist of a contact-in-edge case and a contact-in-corner one, aiming to capture the effect of initial contact on both plastic collapse and energy absorption. Both experimental quasi-static tests and numerical simulation via finite element modeling in LS-DYNA software are carried out for the evaluation of the crushing response of the tested tubes. The 5° oblique cornered crushing revealed the greatest energy absorption, reflecting the most efficient loading case as significant tearing failure occurred around the tube corners in axial crushing due to a higher peak crushing force, while the increase in crushing angle caused a drop in energy absorption and peak force regarding the oblique loading. Finally, an initial contact-in-corner case revealed higher energy absorption compared to both axial and edged oblique loading, while peak force showed a slight decrease with crushing angle in that case. [ABSTRACT FROM AUTHOR]

The machining process of SiC/Al matrix composites is characterized by strong nonlinearity, and thus, there are great challenges resulting from excessive deformation and stress concentration at the tool-workpiece interface in solving such problems. Smoothed particle hydrodynamics (SPH) as a particle-based algorithm can efficiently tackle mesh distortion due to large deformation using finite element method (FEM) for cutting simulations. However, the computational efficiency by SPH is far below the counterpart by FEM. As a result, to address such issues with individual use of SPH or FEM, the coupled SPH-FEM algorithm is presented to calculate large deformation of aluminum matrix using SPH and small deformation of SiC particles using FEM. This paper aims to develop a SPH-FEM coupling model of machining SiC/Al matrix composites and compare the results with an equivalent FE model. A good agreement between numerical results from the SPH-FEM model and those from the FE model is achieved, which shows that the SPH-FEM coupling method is an alternative to FEM for predicting the cutting force, chip formation, and machined surface morphology. The developed SPH-FEM model is also employed to investigate the influence of the cutting parameters including SiC volume fraction, cutting velocity, and uncut chip thickness on the cutting force. Finally, the orthogonal cutting experiments were conducted to validate the presented SPH-FEM model. Numerical results are in good agreement with experimental results, which confirms that SPH-FEM can accurately predict the resulting cutting force and machined surface morphology. [ABSTRACT FROM AUTHOR]

Closed-cell cellular materials gained tremendous interest in their application in aerospace, shipbuilding and defence industries due to their exceptional impact energy absorption and lightweight characteristics. To assess the suitability of these materials in practical utilisation, a proper characterisation in dynamic loading is necessary. This paper investigates closed-cell aluminium foam's deformation behaviour due to low-velocity projectile impact in experimentation and finite element analysis. The collapse mechanism was numerically and empirically examined. The experiment and the finite element analysis were found to be in good agreement. The lowvelocity projectile impact tests were conducted using an instrumented drop-tower with several projectile tips with an impact energy of 105 J. Finite Element modelling using ABAQUS explicit was undertaken. The results reveal that FE modelling of true foam properties using solid geometry has a good correlation with experimental results. In this study, four impactors/indenters (flat-faced, hemispheric, conical, and truncated-conical) were used. A detailed structural collapse during the low-velocity dynamic impact has been explored with XCT data and finite element tools. [ABSTRACT FROM AUTHOR]

This study aims to explore the compressive behavior and energy-absorbing ability of discretely layered foam-filled tubes. Closed-cell zinc, aluminum, and A356 alloy foams manufactured by the casting route are utilized as axial gradient fillers for various configurations of functionally graded structures. The results suggest that the multi-layer foam-filled tubes reveal the multiple quasi-static responses and gradual increase in stress through sequential collapse initiating from the low-density component. By tailoring the foam density and material, the graded foam-filled tubes are promising to regulate the buckling at a desired location and provide better protection. The multi-layer structures generally exhibit superior crashworthiness to the single-layer counterparts, and the maximum quasi-static specific energy absorption of 10.5 J/g is accomplished by the Al‒A356/2FT. The plasticity of multi-layer foam-filled tubes can be described by an asymptotic model based on the density, strength and height ratio of uniform constituents. The drop-weight impact behavior of graded structures can be predicted by finite element modeling in LS-DYNA, and the simulation results are in good agreement with the experiments in terms of dynamic response and crushing pattern. [ABSTRACT FROM AUTHOR]

As the major energy absorption of helicopter in crash, the buffer plays an important role in the safety flight of helicopter. A combined oleo-pneumatic and foam-aluminum helicopter buffer is proposed in this paper. Based on the theoretical calculation model of plastic collapse stress and finite element model, the impact crushing stress-strain of single aluminum foam is calculated and simulated. Then the calculation and simulation results are verified. Furthermore, the theory and simulation model are verified by impact crushing test of single aluminum foam. The dynamic characteristics curve of aluminum foam collapse is integrated into the dynamic model of combined oleo-pneumatic and foam-aluminum landing gear, and the crashworthiness performance simulation analysis is carried out. The results show that the peak load of the combined oleo-pneumatic and foam-aluminum buffer is reduced by 38%, and the buffer efficiency is increased by 12.7%. The crashworthiness performance of helicopter landing gear buffer is improved effectively. [ABSTRACT FROM AUTHOR]

The porosity distribution, which varies through-thickness direction, plays a vital role in affecting the microstructure and mechanical properties of the final product. This study develops numerical and experimental techniques for the analysis of functionally graded nanobeams with porosity (PFGM). Taking a porous polymeric functionally graded structure as an example, a novel beam can be applied to a broad variety of engineering and biomaterial applications. Tensile specimens were prepared using 3D printing, while flexural bending specimens reinforced with 5% (Al/Al2O3) nanomaterial were made using a special system. To study the performance of functionally graded beams with various porosity distributions, numerical solutions were obtained using finite element methods (FEM) and simulations were conducted in ANSYS software. By comparing the obtained results with those obtained from numerical calculations, the experimental solution, including the bending load and midspan deflection, was validated. Additionally, several parameters, such as the porosity parameter, polymer type, and geometrical characteristics, have been studied for their effect on the flexural strength of functionally graded beams. According to the results, it is found that there is a significant effect of the porous parameter and gradient index on the static behavior of functionally graded beams, and nanoparticles enhance bending resistance. [ABSTRACT FROM AUTHOR]

The current distribution in a fresh aluminum electrolytic cell with slotted carbons is investigated by the Finite Element Method (FEM). The effects of the length of slots, la and lc on current distribution were also determined. The maximum local current density and its position do not change with an increase in lc (0 ≤ lc ≤ 200 mm) for a 400 mm slot located 150 mm from the upper surface of the cathode carbon. However, the maximum current density shifts towards the cell center with increasing slot lengths. Current distribution control thus plays a role in optimizing the cathode slot length. [ABSTRACT FROM AUTHOR]

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The hexagonal honeycomb core sandwich panels used in the satellite structure are subjected to severe vibration during launch. Therefore, the amounts of natural frequencies of these panels are of great importance for design engineers. Three-dimensional finite element modeling of the core considering all geometric parameters (i.e., a high-fidelity model) to achieve accurate results is not cost-effective. The honeycomb core is traditionally equivalent to a homogenized continuum core (i.e., a low-fidelity model) using simple analytical relations with ignoring the adhesive layer at the double cell-walls and radius of inclined cell-wall curvature. In this study, analytical formulations are first presented for the prediction of the equivalent elastic properties of a hexagonal aluminum honeycomb with considering all geometric parameters including adhesive layer thickness, cell-wall thickness, inclined cell-wall length, radius of inclined cell-wall curvature at the intersection, internal cell-wall angle, and honeycomb height. Then, two aluminum honeycomb core sandwich beams with free-free boundary conditions are modeled and analyzed in Abaqus finite element software, one with 3D high-fidelity core and the other with 3D low-fidelity core. In order to validate the results of the equivalent model, the modal analysis test was performed and the experimental natural frequencies were compared. The obtained results show a good agreement between the 3D low-fidelity and high-fidelity finite element models and experimental results. In addition, the influence of the above-mentioned geometric parameters has been investigated on the natural frequencies of a sandwich beam. [ABSTRACT FROM AUTHOR]

This research presents a numerical study on vibro-acoustic and sound transmission loss behavior of an aluminum honeycomb core sandwich panel with fabric-reinforced graphite (FRG) composite face sheets. The sandwich theory, which assumes the honeycomb core as an orthotropic structural layer, is applied to investigate the free and forced vibration behavior of the panel. The radiated sound power from the panel is quantified by Rayleigh integral method, and the random diffuse field as an incident sound source is derived based on finite element method with the employment of ACTRAN. A validation between the simulated results and the experimental data published is carried out to demonstrate the accuracy and reliability of the present approach. The comparison between different materials of honeycomb sandwich structures illustrates the advantages of the fabric-reinforced graphite honeycomb sandwich structure over the other types of sandwich structures considered. The effects of different boundary conditions and honeycomb structural geometry properties on the acoustical performance of the stiffness of the FRG panel are also investigated. The approach of the present research provides useful guidance for evaluating and selecting the other honeycomb sandwich panels when the vibratory and acoustic behaviors of the panels are considered. [ABSTRACT FROM AUTHOR]

Emniyet kemeri sistemleri, otomotiv endüstrisinde kullanılan standart güvenlik ekipmanlarındandır. Emniyet kemeri kullanımı sayesinde araç içerisindeki yolcuların güvenlik seviyeleri arttırılmış ve ciddi yaralanmaların önüne geçilmiştir. Özellikle emniyet kemerinin hava yastığıyla birlikte kullanımı sonucunda, yolcuların kafalarının araç kokpitine çarpmasının önüne geçilerek olası travmaların en alt seviyelere indirilmesi hedeflenmektedir. Ancak mevcut emniyet kemeri sistemlerinin kaza sırasında açığa çıkan enerjiyi tam olarak absorbe edemediği anlaşılmıştır. Tam olarak sönümlenemeyen bu kuvvetin araç içerisindeki yolcular üzerinde kaburga kemiği kırıkları, deri üzerindeki morarmalar gibi çeşitli yaralanmalara sebep olduğu gözlemlenmiştir. Bu kapsamda, emniyet kemeri sisteminin mevcut faydalarından ödün vermeden, insan bedeni üzerinde oluşan travmayı minimize edecek bir sönümleme sistemi tasarlanmış ve bu sistem için gerekli olan analizler yapılmıştır. Bahsi geçen bu sönümleme sistemi CATIA yazılımı kullanılarak modellenmiş, gerekli olan analizler ise ABAQUS yazılımı kullanılarak gerçekleştirilmiştir. Sönümleme görevini gerçekleştirecek olan alüminyum köpüğün farklı formları için sonlu elemanlar analizleri yapılmıştır. Analizler sonucunda kesik piramit modelinin optimum sonucu verdiği görülmüştür. Bu çalışmada, emniyet kemeri sistemleri için tasarlanmış olan yeni sönümleme sistemi sayesinde kaza anında açığa çıkan enerji absorbe edilerek, bu enerjinin yolcular üzerindeki çeşitli olumsuz etkilerinin ortadan kaldırılması hedeflenmektedir

Liquid shims are often used to fill tolerance gaps between bolted joint plates in aircraft structures. This paper presents an experimental and numerical study of the effect of liquid shim and pretension on the quasi-static behavior of aluminum joints with titanium bolts. Single shear butt joint specimens with and without liquid shim, and with two levels of bolt pretension, were tested to failure. The experiments were simulated using FE-models which include elastic–plastic material behavior and a ductile damage model. Both the simulations and the experimental tests showed that the level of pretension had a small effect on the failure load. On the other hand, the specimens with liquid shims had a significantly lower strength and stiffness than the specimens without the shims. • FE-modeling of plasticity, damage and failure in bolted joints with liquid shims. • Bolt failure validated by experimental tests. • Liquid shim reduces the strength of the bolted joint. • Pretension has small effect on the joint strength. [ABSTRACT FROM AUTHOR]

• Interpenetrating porous composite structures were prepared by in situ method. • Interfaces with partially metallurgical bonding enhance lobal mechanical properties. • The introduced reinforcement confined the expansion of cracks in composites. • Structural designing is feasible to enhance the mechanical properties of composites. Aluminum foam (AF) has extensive application prospects due to its high specific strength and specific energy absorption. However, low compressive strength and plateau stress of AF limit their total energy absorption. This study introduces a combined way of melt foaming and infiltration casting for fabricating bi-continuous interpenetrating porous composites (BIPCs), which formed partial metallurgical bonding interfaces while ensuring three-dimensional mechanical bond constraints. Four types of three-dimensional structures were designed to reinforce AF. Mechanical behavior of AF and the composites under quasi-static compression was analyzed by combining compressive tests and the finite element method (FEM). The results showed that all reinforcements can efficiently improve the energy absorption of composites by preventing the expansion of cracks in aluminum foam. The structure reinforced along the body diagonal and the path of the center lines connecting the three pairs of parallel surfaces of the cube exhibited the best mechanical properties, whose energy absorption, specific energy absorption and specific compressive strength were 9.58, 3.48 and 2.89 times greater than those of AF, respectively. The critical stress of the rods to buckling and stretching failure of the four configurations were calculated. Results showed that large critical stresses tended to appear in the 1/4 and 1/2 round rods, which revealed that the fracture failure easily occurred at the intersection edges of plane surface and curved surface of struts. [Display omitted] [ABSTRACT FROM AUTHOR]

We investigate the normal impact of a rigid sphere on a half-space of elasto-plastic auxetic/metal foam using the finite element method. The dependence of the coefficient of restitution, peak force, maximum displacement, and contact duration on the yield strain, impact velocity, and elastic and plastic Poisson's ratio is analyzed. For a given elastic Poisson's ratio, the coefficient of restitution generally decreases with an increase in the plastic Poisson's ratio and impact velocity. When the plastic Poisson's is maintained constant, the coefficient of restitution increases with an increase of the elastic Poisson's ratio. These trends are explained using plastic energy dissipation. The energy dissipation trends are further investigated by decomposing it into deviatoric and hydrostatic parts. For a given impact velocity, the peak force is relatively insensitive to most of the elastic and plastic Poisson's ratio combinations. We also show that for the cases where the elastic and plastic Poisson's ratios are equal, the coefficient of restitution is relatively insensitive to their actual values. These findings can guide researchers to identify the right elastic and plastic Poisson's ratio combinations so that lattice materials with exceptional energy absorbing capacity can be designed using topology optimization. [ABSTRACT FROM AUTHOR]

The aim of the research was to develop a new lightweight sandwich structure, which can be used for elements of air containers. The structure consists of aluminum foam core with fiber reinforced composite face-sheets. Nine different laminated glass or/and carbon fiber reinforced plastic face-sheet combinations were investigated. Finite element analysis of the sandwich structures was introduced. Single-objective optimization of the new sandwich structure was achieved for minimal weight. Five design constraints were considered: stiffness of the structure, face-sheet failure, core shear, face-sheet wrinkling, size constraints for design variables. The elaborated composite structure results significant weight savings due to low density. [ABSTRACT FROM AUTHOR]

AlSi10Mg porous alloy was prepared by selective laser melting (SLM) with a Nd:YAG laser beam, and the compression properties were studied using both experiments and the finite element method (FEM). The results illustrate that the porous alloy undergoes elastic deformation, plastic deformation and densification stage. The joints of the porous alloy are preferentially fractured, and the Si content at the bottom position of the dimple is higher than the dimple edge. During the compression process of the porous AlSi10Mg alloy, the stress and strain distribution at the joint are concentrated, resulting in joint fracture. The inherent elasticity, shear stress and forced contact of supporting plates or chips are the causes of these compression stages. The distribution of Si element in the fracture is caused by the dimples that are easily formed at the a-Al/Si interface, eventually resulting in the Si content at the bottom of the dimple being higher than the dimple edge. [ABSTRACT FROM AUTHOR]

Concertina folding of tubes used for impact mitigation bends the tube section to tight curvatures that can lead to failures on the tensioned side of the folds. This paper reports results from such axial crushing experiments on Al-6061-T6 circular tubes in which cleft-like features were also observed on the compressed sides of folds. Microscopic examination of the compressed sides of sectioned folds at different stages of bending revealed the following. Compression leads to surface wrinkles that are initiated by small initial surface roughness. Further bending increases the amplitude of the wrinkles, and at even higher bending the wrinkles morph into folds, creases, and sharp discontinuities. Metallographic examination of these surface undulations revealed that surface wrinkles encompass several grains, which deform conforming to the imposed local geometric changes. With this in mind, the axial crushing was simulated at the continuum level via an axisymmetric finite element analysis coupled with a suitably calibrated non-quadratic elastic–plastic constitutive model. A sufficiently refined mesh and representative initial surface imperfections enabled monitoring of the evolution of surface instabilities on the compressed sides of folds. Surface wrinkles appear at compressive strains of about 50%. As the local bending increases, their amplitude grows, and subsequently they evolve into local folds, and creases that resemble surface features observed in the experiments. [ABSTRACT FROM AUTHOR]

The effect of cut‐outs positions and shapes on deformation behaviors and energy absorption of automobile thin‐walled structures is researched by quasi‐static axial compression, using MTS machine and digital image correlation method. The accuracy of finite element modeling is verified by axial compression test. The relationship between variation characteristics of different time and sections and deformation of the sample is analyzed. The results show that the number of surface deformation concentrated areas is affected by position of circular cut‐outs. Peak load of sample could be effectively reduced by slotted‐shaped cut‐outs. The energy absorption of slotted‐shaped cut‐outs with different aspect ratios and directions is different, horizontally‐long‐slotted cut‐outs is increased by 5.13 %. The position of deformation concentration region is affected by compression half‐wavelength. Deformation concentration region of sample less than half‐wavelength is below cut‐outs. By digital image correlation method, strain of horizontally‐long‐slotted cut‐outs is more concentrated. Peak load is effectively reduced. The results of finite element analysis show that when the thin‐walled structure is bulking, the section of sample is deformed from top to bottom. The initial area of cross‐section at center of cut‐outs is linear with peak load. These achievements may serve as guideline for enhancing compression performance of thin‐walled structures. [ABSTRACT FROM AUTHOR]

A method for strengthening damaged tubular steel T-joints under axial compression by wrapping them with carbon fiber-reinforced polymer (CFRP) sheets was proposed and evaluated. The influence of the CFRP strengthening on the failure mode and load capacity of T-joints with different degrees of damage was investigated using experiments and finite element analyses. Five T-joints were physically tested: one bare joint to obtain the peak load and corresponding displacement (Δ1m), two reinforced joints to provide a reference, and two pre-damaged then retrofitted joints to serve as the primary research objects. The ratio of the pre-loaded specimen chord displacement to the value of Δ1m was considered to be the degree of damage of the two retrofitted joints, and was set to 0.80 and 1.20. The results demonstrate that the maximum capacity of the retrofitted specimen was increased by 0.83%–15.06% over the corresponding unreinforced specimens. However, the capacity of the retrofitted specimen was 2.51%–22.77% lesser compared with that of the directly reinforced specimens. Next, 111 numerical analysis models (0.63 ⩽ β ⩽ 0.76, 9.70 ⩽ γ ⩽ 16.92) were established to parametrically evaluate the effects of different geometric and strengthening parameters on the load capacity of strengthened tubular T-joints under different degrees of damage. The numerical analysis results revealed that the development of equivalent plastic strain at the selected measuring points was moderated by strengthening with CFRP wrapping, and indicated the optimal CFRP strengthening thickness and wrapping orientation according to tubular T-joint parameters. Finally, reasonable equations for calculating the load capacity of CFRP-strengthened joints were proposed and demonstrated to provide accurate results. The findings of this study can be used to inform improved CFRP strengthening of damaged tubular steel structures. [ABSTRACT FROM AUTHOR]

• Implosion tests are conducted using water only and the combination of water and nitrogen gas. • The ovality and thickness unevenness of the test models are measured. • The effects of pressurising rates on the ultimate strength of the test models are investigated. • Dynamic pressures in terms of short duration pulses are also monitored during the collapse event. • The effect of geometric parameters on the ultimate strengths are numerically conducted. Experimental studies are conducted to investigate the implosion characteristics of thin cylindrical aluminium-alloy tubes. The effects of various parameters that generate different responses on the implosion behaviours are investigated. Aluminium-alloy tubes are fabricated from a 6061-T6 material and designed in the range of 2.5–6.7 length-to-diameter ratios; wall thickness-to-diameter ratios are varied from 55 to 69. The geometric imperfection parameters, defined as the initial ovality and thickness unevenness, are considered. Two different pressurising media, i.e., water only and the combination of water and nitrogen gas are employed. In addition small- and medium-sized of pressure chamber are utilised to clarify the pressure drop after the ultimate strength reached. Furthermore, non-linear finite element analyses, benchmarked for quantitative validation and comparison of the imploded tubes, are conducted. The numerical benchmark quantities are initial ovality, thickness unevenness, and air-backed fluid cavity parameters. The results of these experiments indicated that the effects of combined water and nitrogen can reproduce a constant pressure environment similar as actual undersea conditions, but the combined pressuring media can reduce the pressuring rate. [ABSTRACT FROM AUTHOR]

Aluminum is a light, strong, and corrosion-resistant material. Its extruded form, the aluminum extruded panel, consists of two aluminum plates with truss core, which can be applied in a wide range of engineering areas. In this work, the structureacoustic coupling finite element method (FEM) is employed to analyze the sound transmission through high-speed train (HST) aluminumextruded panels. The automatically matched layer (AML) is used to simulate the non-reflective boundary condition. It is found that the predicted sound transmission loss (STL) is in good agreement with the experimental results and the prediction accuracy of the finite element method can be further verified. Based on this proposed method, a parametric study is carried out to investigate how the structure parameters affect the STL. The results suggest that the rib angle exhibits a greater effect on STL in the abovemiddle frequency areawhere themodal density is high. The increase in the height between the panels will lead to a higher STL overall value of the aluminum extruded panel and make the STL dips move toward higher frequencies, while the increase of the rib thickness will drive the STL dips to an opposite direction. Finally, the STLs of the aluminumextruded panel in different regions of the train body are comprehensively analyzed. The highest overall value of STL is found in the flat-top region, whereas the lowest value appears in the curve-top region. Overall, the results in this article can provide valuable implications for the noise performance optimization of HST. [ABSTRACT FROM AUTHOR]

This article presents the numerical tests of thin-walled compressed columns with a square cross-section. The crush efficiency indicators were determined using the finite element method (Abaqus) and neural networks of MLP. The models had a constant circular trigger, with a diameter of 32 mm. During dynamic analysis, the samples were loaded with 1700 J. The numerical models were filled with aluminum foam from 40 mm to 180 mm every 20 mm. The study presents the conclusions for the thin-walled models with crushable foam. [ABSTRACT FROM AUTHOR]

Macroporous metal foams are used as energy exchange materials and have been widely used in the industry. In this paper, the finite element method is used to calculate the equivalent thermal radiation conductivity and equivalent thermal conduction equivalent conductivity of the fractal-skeleton heat transfer model, and the heat transfer characteristics of the two components are analyzed. The results show that during thermal conduction progress, energy transfer mainly occurs at the junction of walls and holes perpendicular to the direction of heat flow. While during the thermal radiation process, the smaller the cell wall thickness and the larger the porosity, the larger the proportion of the heat radiation conductivity in the total heat conductivity. When the structural size is equal to the characteristic wavelength, the scattering coefficient is rapidly reduced, so that the radiation heat transfer effect is improved. Finally, the cause of this phenomenon is further explained by the micro-mechanism theory. [ABSTRACT FROM AUTHOR]

Open cell metal foams are interesting lightweight materials, which are used in a variety of applications. Effected by the complex microstructure of open cell metal foams the macroscopic material behaviour cannot be described with a von Mises yield criterion. In comparison to bulk metals, open cell metal foams collapse under hydrostatic compression and tension. Modelling of this behaviour is realised by using a closed yield surface to describe the plastic behaviour. This contribution considers the asymmetric yield surfaces measured for open cell metal foams with 10 and 20 ppi. A Finite Element implementation of a single closed yield surface is introduced. Furthermore, a new approach to identify the material parameters of the yield surface as well as the structural Young's and hardening moduli is introduced. The simulations are realised with a Finite Element Method and the numerical results are compared with the experiments. The numerical results are fitted to the experimental data by modifying the material parameters of the model in an iterative optimisation process. The optimised material parameters are used to describe different loading conditions for open cell aluminium foams. The results of the simulation are compared with the multiaxial experiments for the sake of validation. [ABSTRACT FROM AUTHOR]