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Nowadays, composite sandwich tubes are extensively utilized in the civil and aerospace industries due to their superior strength-to-weight mechanical properties. Origami-based core offers a large enhancement of the mechanical properties, yet little study research focuses on the effect of various foldcore configurations on the transverse mechanical properties of sandwich tubes, necessitating the design method for applications. This study introduces an innovative approach by incorporating origami into the composite sandwich core to enhance the transverse energy absorption capacity. The quasi-static transverse mechanical properties of carbon fibre-reinforced polymer (CFRP) sandwich tubes with foldcores are studied under three-point bending-like local compression and transverse structural compression. A systematic geometric design framework and numerical modelling technique are provided. By integrating finite element analysis and experiments, the research investigates the effects of various origami foldcore configurations and geometric parameters on transverse energy absorption capacity. The experiment setup is provided by sandwich tubular specimens with a full-diamond configuration as the foldcore. The cylindrical tubes (foldcore) of the sandwich structures were manufactured using four plies [0°]4 of T700 (T300) woven CFRP with the hot press moulding (vacuum bag using female and male moulds) technique respectively. Then, the parametric study and damage mode analysis of eight different foldcore patterns (axial Miura, circumferential Miura, diamond, Kresling, and their curved-creased counterparts) were studied. The results showed the superior energy absorption performance of the sandwich tube with Miura-pattern foldcore over the origami-pattern counterparts, nested tube, and traditional honeycomb sandwich tube with CFRP or aluminium-made cores. Therefore, the structural parameters optimisation of the Miura pattern tube was carried out by the Response Surface method (RSM) and a design strategy for increasing the energy absorption capacity was found. The findings offer guidance for designing high-specific energy absorption tubular structures for future advanced engineering applications. [ABSTRACT FROM AUTHOR]

AbstractLightweight, energy-absorbing materials with superior mechanical properties are vital for engineering. Interpenetrating phase composites (IPCs) of Al2O3 ceramic and epoxy resin exhibit enhanced performance via non-homogeneous lattice design. Compression tests showed over 60% strength improvement compared to single-phase materials, while bending tests highlighted greater load capacity. Non-homogeneous structures demonstrated superior energy absorption and load-bearing abilities. Epoxy resin enhanced toughness under compression but not bending. A bulletproof model validated the practical potential of IPCs, emphasizing their engineering applicability in optimizing material properties through tailored lattice designs. [ABSTRACT FROM AUTHOR]

Multicellular, thin‐walled impact tubes have been intensely studied and used in various engineering fields in recent years due to their lightweight, high performance, ease of application, superior energy absorption, and stable deformation characteristics. In this study, energy absorption, crashworthiness performances, and deformation properties of thin‐walled structures manufactured from polylactic acid (PLA+) and acrylonitrile butadiene styrene (ABS) using fused deposition modeling (FDM) technology were compared under quasi‐static axial compression. Thin‐walled structures consist of multicellular tubes connected by concentric corner‐edge connections with square and hexagonal cross‐sections. Experimental testing outcomes indicate that the energy absorption capacity increases with increasing the number of corners in multicellular structures. The tubes with square wall‐to‐wall (S‐WW) and hexagonal wall‐to‐wall (H‐WW) cross‐sections exhibit superior crashworthiness performance compared to other cross‐sections. Based on the experimental results, the absorbed energy by WW patterned PLA+ square tubes are 19%, 7%, and 46% more than that of wall‐to‐corner (WC), corner‐to‐wall (CW), and corner‐to‐corner (CC) patterned tubes, respectively, while it is 11%, 19%, and 80% more in hexagonal cross‐section tubes, respectively. This study provides an informative reference for easier applicability of multicellular energy‐absorbing structures with 3D‐print and the design of corner‐edge connections of internal connections in multicellular structures. [ABSTRACT FROM AUTHOR]

The present study aims to enhance the energy absorption performance of Twaron aramid fabrics by impregnating them with single and multi-solid phase shear thickening fluids (STFs). To investigate the energy absorption capacity of Twaron 200 and Twaron 460 fabrics, surface friction, yarn tensile, and ballistic tests have been performed. Silicon carbide (SiC), graphene nanoplate (GNP), and carbon nanotube (CNT) are utilized both individually and in hybrid forms to examine the impact of multi-solid phase STFs. The research reveals that STFs reinforced with SiC and GNP exhibit higher viscosity and rheological behavior compared to other hybrid nanoparticles. The addition of SiC and GNP reinforced STF (STF/SiC + GNP) suspension significantly increases the friction coefficient by approximately 82% for Twaron 200 and 120% for Twaron 460 in comparison to neat fabric. Moreover, the maximum yarn tensile strength of Twaron 460 is higher than that of Twaron 200 in both neat and STF impregnated fabrics. The research also states that STF impregnation procedure improves the ballistic performance of neat fabrics in both fabric types. The ballistic test results show an increase in the protective performance of STF impregnated fabrics reinforced with nanoparticles. The best ballistic performance is found in STF/SiC + GNP impregnated fabrics in Twaron 200 and Twaron 460 samples. [ABSTRACT FROM AUTHOR]

Abstract Conventional energy-absorbing components have limitations in terms of performance and functionality, including significant variability in reaction forces, inherent instability, and inadequate energy absorption capabilities. This paper presents a threaded shear-type energy-absorbing component designed for anti-impact hydraulic support columns, specifically for ZQL advancing support roadway hydraulic supports. The component operates based on the principle of threaded shear energy absorption. Its key structural parameters—such as thread shape, outer diameter, and pitch—are optimized using single-factor and response surface experimental design methods. Shear simulations are performed to analyze the deformation and force-displacement characteristics across various structural configurations. The impact of different thread parameters on energy absorption performance is evaluated, with quasistatic shear tests and simulations validating the results. The optimized design enhances energy absorption efficiency and provides a foundation for future research on integrating these components into hydraulic support systems to improve overall performance.

This study investigates the flexural behavior of 3D-printed multi-topology lattice beams, with a specific emphasis on octet and cube lattice geometries created through fused deposition modeling (FDM). The mechanical properties of these beams were evaluated through quasi-static three-point bending tests. A comparative analysis of load-carrying capacity, energy absorption, and specific energy absorption (SEA) indicates that octet lattice beams exhibit superior performance to cube lattice beams. The octet lattice beam in the triple-layer double-column (TL-DC) arrangement absorbed 14.99 J of energy, representing a 38% increase compared to the 10.86 J absorbed by the cube lattice beam in the same design. The specific energy absorption (SEA) of the octet beam was measured at 0.39 J/g, which exceeds the 0.29 J/g recorded for the cube beam. Two distinct types of deformations were identified for the struts and the beam layers. Octet struts exhibit enhanced performance in stretch-dominated zones, whereas the cube system demonstrates superior efficacy in compressive-dominated regions. The results highlight the enhanced efficacy of octet lattice structures in energy absorption and mechanical stability maintenance. The investigation of sandwich lattice topologies integrating octet and cube structures indicates that while hybrid designs may exhibit efficiency, uniform octet structures yield superior performance. This study provides valuable insights into the structural design and optimization of lattice systems for applications requiring high-energy absorption and mechanical robustness. [ABSTRACT FROM AUTHOR]

In comparison to monolithic materials, cellular solids have superior energy absorption capabilities. Of particular interest within this category are the periodic lattice materials, which offer repeatable and highly customizable behavior, particularly in combination with advances in additive manufacturing technologies. In this paper, the crashworthiness of engineering multi-layer, multi-topology (MLMT) resin lattices is experimentally examined. First, the response of a single- and three-layer single topology cubic and octet lattices, at a relative density of 30%, is investigated. Then, the response of MLMT lattices is characterized and compared to those single-topology lattices. Crashworthiness data were collected for all topology arrangements, finding that while the three-layer cubic and octet lattices were capable of absorbing 9.8 J and 7.8 J, respectively, up to their respective densification points, the unique MLMT lattices were capable of absorbing more: 19.0 J (octet-cube-octet) and 22.4 J (cube-octet-cube). These values are between 94% and 187% greater than the single-topology clusters of the same mass. [ABSTRACT FROM AUTHOR]

As an important part of head protection equipment, research on the material and structural application of helmet liners has always been one of the hotspots in the field of helmets. This paper first discusses common helmet liner materials, including traditional polystyrene, polyethylene, polypropylene, etc., as well as newly emerging anisotropic materials, polymer nanocomposites, etc. Secondly, the design concept of the helmet liner structure is discussed, including the use of a multi-layer structure, the addition of geometric irregular bubbles to enhance the energy absorption effect, and the introduction of new manufacturing processes, such as additive manufacturing technology, to realize the preparation of complex structures. Then, the application of biomimetic structures to helmet liner design is analyzed, such as the design of helmet liner structures with more energy absorption properties based on biological tissue structures. On this basis, we propose extending the concept of bionic structural design to the fusion of plant stalks and animal skeletal structures, and combining additive manufacturing technology to significantly reduce energy loss during elastic yield energy absorption, thus developing a reusable helmet that provides a research direction for future helmet liner materials and structural applications. [ABSTRACT FROM AUTHOR]

Due to their lightweight features and special energy absorption properties, metal foams (MFs) are gradually replacing fully-dense solid materials in top industries. Having a porous structure with thin cell-walls, MFs are quite sensitive to various operating conditions such as temperature (TT) and loading direction (LD), aspects that should not be neglected. However, the dual TT-LD impact on the mechanical behavior of anisotropic MFs has not yet been addressed. In this regard, the temperature range 25–550 °C (in steps of 75 °C) and the three orthogonal directions (X, Y and Z) were used to experimentally investigate the compressive crushing responses of MFs under the combined temperature-anisotropy effect. The studied MFs had closed cells and were manufactured from Al alloys (AlSi12Mg0.6) through powder metallurgy route. The main strength properties and energy absorption performance of the investigated foams were found to be strongly dependent on the LD and the TT. The best mechanical characteristics are highlighted by the Z-LD, followed in order by the Y and X directions. Thus, improvements in properties were obtained by over 45% (compressive modulus), 71% (compressive strength), 28% (densification strain) and 53% (energy absorption) for Z-LD compared to the other two LDs. Finally, the failure mechanisms differ considerably depending on the imposed test condition (TT or LD).

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For a long time, the extremely high chemical activity of magnesium melt with ceramics at high temperatures makes it challenging to synthesize Mg-matrix syntactic foams (MgSFs) by casting. In this work, for the first time, high porosity of AZ31B magnesium alloy matrix syntactic foams containing Al2O3 hollow spheres (Al2O3-HS) were successfully synthesized by gravity infiltration casting. The Al2O3-HS were coated with MgO using MgCl2 solution after high-temperature calcination to prevent the interfacial reaction. The results show that the concentration of the MgCl2 solution strongly influences the porosity of the syntactic foams because it determines the coverage of Al2O3-HS with the MgO coating and the survival of particles. The maximum porosity of the syntactic foam was 41.64 vol%, and the corresponding density was 1.17 g/cm3. At the MgCl2 solution coating concentration of 0.15 g/ml, the plateau stress of the syntactic foam reaches the maximum value of 55.96 MPa, the energy absorption capacity was 39.27 MJ/m3, and the maximum energy absorption was 26.06 kJ/kg. These properties are comparable to some MgSFs prepared by other methods in recent years.

In recent years, negative Poisson′s ratio（NPR） materials have attracted extensive attention from the academic community due to their excellent mechanical properties and huge application potential in traditional industrial fields. The mechanical properties of a new type of material with negative Poisson′s ratio（based on YSH structural cell） under dynamic compression are designed and studied. Through the finite element simulation method, the response difference of different structural parameters（inclined wall angle, width ratio, aspect ratio） to the equivalent elastic mechanical performance parameters of the cell is compared, and the influence of these structural parameters on the energy absorption performance is explored, and the research is further extended to the structure under four common functional gradient arrays. The energy absorption effect of the structure is evaluated by three indexes: energy absorption, energy absorption efficiency and platform stress. The study shows that, inclined wall inclination θ the larger, the better the energy absorption performance of the whole structure; width ratio α it has little influence on the equivalent mechanical properties and energy absorption of the whole structure; aspect ratio β the smaller the value, the more obvious the negative Poisson′s ratio effect of the structure, but on the contrary, the larger the value, the higher the energy absorption efficiency. The results can provide a reference for the function-oriented design of materials with negative Poisson′s ratio.

Copyright of Journal of Mechanical Strength / Jixie Qiangdu is the property of Zhengzhou Research Institute of Mechanical Engineering 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.)

Thin-walled tubes are widely used as passive energy-absorbing structures in a variety of industries. These structures are typically filled with lightweight materials to improve their energy absorption capabilities. At this point, additive manufacturing technology offers a great chance researchers for the production of novel filler structures to increase the crashworthiness performance of thin-walled tubes. In the current work, additive manufacturable body-centered cubic (BCC) lattice structures are suggested as filling materials for thin-walled tubes, and the bending response of these structures is investigated under transverse loads via a finite element modeling approach. The aspect ratio and strut diameter are considered as design parameters, and three-point bending simulations are conducted to understand the transverse load bearing behaviors of the structures. Different loading offsets are also taken into account for three-point bending simulations. The numerical results revealed that the BCC lattice structures used as filler materials significantly increase the energy absorption performance of thin-walled tubes due to synergetic interactions. In particular, the simulation results revealed that the hybrid tubes can absorb up to 84% more energy than the empty tubes, while the crush force efficiency of these structures is up to 42% higher compared to the empty tubes. The present study also showed that the transverse crushing characteristics of tubes can be considerably improved by suitable selection of the design parameters. These primary outcomes reveal that the proposed lattice structures can be considered as a potential alternative to traditional filler materials for enhancing the bending response of thin-walled tubes under transverse loading.

• A novel polygonal asymmetric origami tube (PAT) is designed to produce more traveling plastic hinge lines. • The deformation process of the PAT is verified through axial crushing experiments, numerical models, and impact experiments, and the deformation mechanism is summarized. • The deformation theory analysis demonstrates that the PAT can realize hierarchical deformation and avoid stress concentration at sharp corners. • The average crushing force of PAT is analyzed and predicted by theoretical analysis. Origami tubes have attracted widespread attention because it is inclined to deform in the complete diamond mode (DM) with a low initial peak force F max and high average crushing force F ave. Although conventional origami tubes can improve crashworthiness, there are still many areas that fail to generate traveling plastic hinge lines, and the crashworthiness can be further improved. This paper presents a novel polygonal asymmetric origami tube (PAT) with origami patterns that can trigger more traveling plastic hinge lines compared to those of conventional origami patterns. The theoretical analysis of the deformation mechanism suggests that the PAT can realize hierarchical deformation and avoid stress concentration at sharp corners. The quasi-static experiments and numerical simulations reveal that the novel origami pattern can successfully trigger up to four times more traveling plastic hinge lines than the conventional square box (CSB) under the premise that each plastic hinge line is similar in length. Compared with the CSB, the PAT can deform in DM with a 56.0 % reduction of F max and a 59.1 % increase of F ave. Notably, the stableness of load-carrying capacity SLC is 90.2 %, which is 260.8 % higher than the CSB. A series of parametric studies reveal that the dihedral angle ratio α / β and the width-to-thickness ratio c / t of the PAT have a significant effect on crashworthiness. A smaller ratio of α / β and c / t provides the PAT with superior crashworthiness. Comparing the PAT with other types of origami tubes and multi-cell tubes indicates that the PAT also exhibits outstanding crashworthiness. The impact experiments also unveil a significantly enhanced crashworthiness of the PAT. Compared with the CSB, the F max decreases by approximately 46.4 %, while the F ave increases by around 92.7 %. The SLC and SEA values for the PAT surpass those of the CSB by about 260.8 % and 93.1 %, respectively. Furthermore, the theoretical analysis for predicting the F ave of the PAT is developed, with a maximum error not exceeding 8.5 %. [Display omitted] [ABSTRACT FROM AUTHOR]

In this research, the rheological behavior of shear thickening fluid (STF), produced using many nanoparticles, has been investigated. Fumed silica, multi-walled carbon nanotube (MWCNT), graphene nanoplate (GFNP), and silicon carbide (SiC) nanoparticles have been used in the production of the hybrid sample. In the rheological test results, it has been preferred because it is successful in the production of hybrid shear thickening fluid (HSTF), 25 wt.% by the mixture of Aerosil 150, and polyethylene glycol 400 (PEG 400). Different particle sizes of each nanoparticle have been determined by adding MWCNT, GFNP, and SiC nanoparticles to HSTF. In the production of HSTF, the highest performance is found in MWCNT (0.3 wt.%), SiC (0.2 wt.%), and GFNP (0.1 wt.%) when each nanoparticle is used as a single, double, or triple. The stab resistance of Twaron fabrics is also investigated in a drop tower against spike and knife impactors. It is understood that HSTF-impregnated Twaron fabrics have a positive effect on energy absorption performance. The energy absorption performance of HSTF-impregnated Twaron fabrics is found to be more effective than STF-impregnated Twaron fabrics. [ABSTRACT FROM AUTHOR]

Due to their lightweight, porous and excellent energy absorption characteristics, foam and honeycomb materials have been widely used for filling energy absorbing devices. For further improving the energy absorption performance of the novel tube proposed in our recent work, the nonlinear dynamics software Abaqus was firstly used to establish and verify the simulation model of aluminum-filled tube. Then, the crashworthiness of honeycomb-filled tubes, foam-filled tubes and empty tube under axial load was systematically compared and analyzed. Furthermore, a comparative analysis of the mechanical behavior of filled tubes subjected to bending load was carried out based on the study of dynamic response curve, specific energy absorption and deformation mechanism, the difference in energy absorption performance between them was also revealed. Finally, the most promising filling structure with excellent crashworthiness under lateral load was optimized. The research results show that the novel thin-walled structures filled with foam or honeycomb both show better energy absorption characteristics, with an increase of at least 8.8% in total absorbed energy. At the same time, the mechanical properties of this kind of filled structure are closely related to the filling styles. Foam filling will greatly damage the weight efficiency of the novel thin-walled tube. However, honeycomb filling is beneficial to the improvement of SEA, which can be improved by up to 18.2%. [ABSTRACT FROM AUTHOR]

To obtain the lattice structure with excellent energy absorption performance, the structure of loofah inner fiber is studied to develop bionic design of lattice structure by experiment and simulation analysis method. From the compression experiment about the four bionic multi-cell lattice structures (bio-45, bio-60, bio-75, and bio-90) and VC lattice structures, we found that all are made of PLA and fabricated by the fused deposition modeling (FDM) 3D printer. The comprehensive performance of bio-90 lattice structure is the best in the performance of the specific volume energy absorption (SEAv), the effective energy absorption (EA), and the specific energy absorption (SEA). Based on the experimental result, the energy absorption performance of bio-90 lattice structure is then studied by the simulation analysis of influence on multiple parameters, such as the number of cells, the relative density, the impact velocity, and the material. The results can provide a reference for the design of highly efficient energy absorption structures. [ABSTRACT FROM AUTHOR]

To overcome the poor energy-absorbing efficiency of existing layered panels, three kinds of novel steel-glass fiber reinforced polymer (GFRP)-foam sandwich structures composed of two steel face sheets and GFRP-foam composite cores were proposed in this paper. The effect of the composite core thickness and GFRP lattice configuration on the energy absorption performance for sandwich structures was studied through quasi-static crushing tests. Considering the role of steel face sheets, a theoretical prediction model was derived to calculate the initial absorbed energy for all types of sandwich panels. Parametric studies were carried out to investigate the influence of five different variables (axial compressive load, steel sheet thickness, GFRP web thickness, GFRP and foam compressive modulus) on the overall energy dissipation for each kind of composite panel. Test results indicated that both the thicker core component and double-layered dislocation GFRP layout could effectively promote the energy consumption property of all the steel-GFRP-foam structures, and the steel face sheet played a crucial role in the proposed sandwich panels due to its excellent absorbed-energy capacity per volume and exceptional ductility. Theoretical results demonstrated that the equivalent energy-absorbing formula was desirable to be used to assess the crushing resistant behavior of each sandwich structure. Parametric analysis results showed that a larger axial compressive load was able to improve the structural initial energy absorption, but the increase of four other structural parameters, especially the thickness of the front (rear) steel sheet, could weaken such an identical performance. • Three types of innovative steel-GFRP-foam sandwich structures were proposed to promote the overall energy-absorbing efficiency. • Quasi-static crushing experiments were taken to investigate the energy absorption performance of steel-GFRP-foam structures. • A theoretical model was firstly established to predict the initial absorbed energy of steel-GFRP-foam sandwich panels. • Parametric studies were conducted to discuss the effect of various structural indicators on the energy dissipation of steel-GFRP-foam panels. [ABSTRACT FROM AUTHOR]

• A novel woven metallic lattice (WML) with orthogonal spiral wires is proposed. • Multiple stress plateaus can be achieved in the WML structure. • Energy absorption performance of WML structure under quasi-static compression is analyzed in detail. • The structures with a gradient in cell parameters exhibit a specific deformation characteristics. Woven metallic lattice (WML) structures are gaining attention for their beneficial mechanical properties, such as low weight and special energy absorption capability. They hold potential for diverse applications, including energy absorption components in aerospace. Drawing inspiration from the traditional double-arrow lattice, this study proposes a novel WML design featuring multi-plateau stresses. The deformation behavior of this structure under compression was investigated using finite element analysis and experimental methods. Three gradient structures defined by the different layer arrangements along load direction associated with specific structure variables, namely positive gradient (PG), negative gradient (NG), and hybrid gradient (HG), were introduced, along with an examination of their mechanical properties. The study explored the influence of key parameters of the cell structure on compression characteristics. Findings suggest that enhancing cell vertex angle and wire diameter can improve energy absorption, while the opposite holds true for cell base angle. Among the gradient structures analyzed, the PG WML structure demonstrates optimal energy absorption due to its dual-plateau stress characteristics. The NG WML structure is noteworthy for its uniform lattice deformation during initial compression stages, which is crucial for precision engineering with subtle deformation control strategies. Lastly, the deformation pattern of the HG WML structure during compression progresses from low to high strength. [Display omitted] [ABSTRACT FROM AUTHOR]

Thin-walled tubes are widely used as passive energy-absorbing structures in a variety of industries. These structures are typically filled with lightweight materials to improve their energy absorption capabilities. At this point, additive manufacturing technology offers a great chance researchers for the production of novel filler structures to increase the crashworthiness performance of thin-walled tubes. In the current work, additive manufacturable body-centered cubic (BCC) lattice structures are suggested as filling materials for thinwalled tubes, and the bending response of these structures is investigated under transverse loads via a finite element modeling approach. The aspect ratio and strut diameter are considered as design parameters, and three-point bending simulations are conducted to understand the transverse load bearing behaviors of the structures. Different loading offsets are also taken into account for three-point bending simulations. The numerical results revealed that the BCC lattice structures used as filler materials significantly increase the energy absorption performance of thin-walled tubes due to synergetic interactions. In particular, the simulation results revealed that the hybrid tubes can absorb up to 84% more energy than the empty tubes, while the crush force efficiency of these structures is up to 42% higher compared to the empty tubes. The present study also showed that the transverse crushing characteristics of tubes can be considerably improved by suitable selection of the design parameters. These primary outcomes reveal that the proposed lattice structures can be considered as a potential alternative to traditional filler materials for enhancing the bending response of thin-walled tubes under transverse loading. [ABSTRACT FROM AUTHOR]

A joining and forming integrated process for high-strength steel/CFRP multi-material parts was developed, where the hot stamping technology was used to join the high-strength steel and CFRP prepreg. The preparation processes of multi-material composite parts under different quenching temperatures during hot stamping were studied and microscopic observation of the steel sheets was conducted. Then the three-point bending tests for the multi-material composite parts were carried out. The microscopic observation results show that the microstructure of the steel sheets is full martensite. The three-point bending tests indicate that the bending angles of the samples with no CFRP, with two layers CFRP, and with four layers CFRP are as 130°, 110° and 104°, respectively. Besides, the force-displacement curves of the bending tests were integrated to calculate the energy absorption of the samples. The results show that the energy absorption of the samples with no CFRP, with two layers CFRP, and with four layers CFRP are as 9410 J, 9692 J, and 10050 J. The energy absorption of the samples with two-layer CFRP and the samples with four-layer CFRP increase by 2.9% and 6.8% compared with the samples without CFRP. [ABSTRACT FROM AUTHOR]

Due to their lightweight, porous and excellent energy absorption characteristics, foam and honeycomb materials have been widely used for filling energy absorbing devices. For further improving the energy absorption performance of the novel tube proposed in our recent work, the nonlinear dynamics software Abaqus was firstly used to establish and verify the simulation model of aluminum-filled tube. Then, the crashworthiness of honeycomb-filled tubes, foam-filled tubes and empty tube under axial load was systematically compared and analyzed. Furthermore, a comparative analysis of the mechanical behavior of filled tubes subjected to bending load was carried out based on the study of dynamic response curve, specific energy absorption and deformation mechanism, the difference in energy absorption performance between them was also revealed. Finally, the most promising filling structure with excellent crashworthiness under lateral load was optimized. The research results show that the novel thin-walled structures filled with foam or honeycomb both show better energy absorption characteristics, with an increase of at least 8.8% in total absorbed energy. At the same time, the mechanical properties of this kind of filled structure are closely related to the filling styles. Foam filling will greatly damage the weight efficiency of the novel thin-walled tube. However, honeycomb filling is beneficial to the improvement of SEA, which can be improved by up to 18.2%.

To obtain the lattice structure with excellent energy absorption performance, the structure of loofah inner fiber is studied to develop bionic design of lattice structure by experiment and simulation analysis method. From the compression experiment about the four bionic multi-cell lattice structures (bio-45, bio-60, bio-75, and bio-90) and VC lattice structures, we found that all are made of PLA and fabricated by the fused deposition modeling (FDM) 3D printer. The comprehensive performance of bio-90 lattice structure is the best in the performance of the specific volume energy absorption (SEAv), the effective energy absorption (EA), and the specific energy absorption (SEA). Based on the experimental result, the energy absorption performance of bio-90 lattice structure is then studied by the simulation analysis of influence on multiple parameters, such as the number of cells, the relative density, the impact velocity, and the material. The results can provide a reference for the design of highly efficient energy absorption structures.

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department 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.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology 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.)

Al2O3 hollow particles were used to manufacture 7055 Al-matrix syntactic foams using a simple gravity infiltration casting method. The effects of infiltration temperature and heat treatment process on microstructures, compressive properties, and energy absorption properties of the prepared Al-matrix syntactic foams were studied. The average density and porosity of the Al-matrix syntactic foams are 1.73 g cm-3 and 40.89 %, respectively. The maximum compressive yield strength and compressive strength of the as-cast Al-matrix syntactic foams are 78.23 and 79.52 MPa, respectively. After solution-aging treatment, the compressive strength and yield strength of the Al-matrix syntactic foams are significantly improved. After normalizing, the average compressive plateau stress and energy absorption performance are the best. The highest energy absorption capacity and specific energy absorption are 48.14MJ m-3 and 28.04 kJ kg-1, respectively. This result reached or exceeded the energy absorption properties of many Al-matrix syntactic foams prepared by other processes reported in recent years. [ABSTRACT FROM AUTHOR]

In order to study the impact resistance and failure mode of aluminum alloy triangular corrugated sandwich plates impacted by blunt-nosed projectiles, the numerical simulation model of plates impacted by projectiles were established by finite element software ABAQUS/Explicit, and also he validity of the model and its parameters were verified by tests. Based on the results of numerical simulation, the influence laws and mechanism of the geometry on the protection performance, failure mode and energy absorption of triangular corrugated sandwich plates were analyzed, and also compared with monolithic plates of the same area density. The results show that the structure of target has effects on the impact resistance, and also the impact resistance of triangular corrugated sandwich plates is lower than that of monolithic plates. Moreover, the impact resistance of triangular corrugated sandwich panels may be significantly improved by increasing the angles of the core topology, and the geometrical sizes of the plates also affect the failure mode and energy dissipation characteristics. [ABSTRACT FROM AUTHOR]

Railway vehicles are generally operated by connecting several vehicles in a row. Mechanisms connecting railway vehicles must also absorb front and rear shock loads that occur during a train’s operation. To minimize damage, rail car couplers are equipped with a buffer system that absorbs the impact of energy. It is difficult to perform a crash test and evaluate performance by applying a buffer to an actual railway vehicle. In this study, a simulation technique using a mathematical buffer model was introduced to overcome these difficulties. For this, a model of each element of the buffer was built based on the experimental data for each element of the coupling buffer system and a collision simulation program was developed. The buffering characteristics of a 10-car train colliding at 25 km/h were analyzed using a developed simulator. The results of the heavy collision simulation showed that the rubber buffer was directly connected to the hydraulic shock absorber in a solid contact state, and displacement of the hydraulic buffer hardly occurred despite the increase in reaction force due to the high impact speed. Since the impact force is concentrated on the vehicle to which the collision is applied, it may be appropriate to apply a deformation tube with different characteristics depending on the vehicle location.

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology 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.)

Aluminium alloy foams are often used as cushioning parts for automobiles because of their excellent energy absorption properties and lightweight characteristics. Their energy absorption properties mainly depend on the cell structure of the foam, but the cell structure of aluminium alloy foams prepared by the powder metallurgy method is usually difficult to control. In this work, Al 3 Ti/Al6061 foam composite (AT-FC) was prepared by powder metallurgy using TiH 2 as the blowing agent and a mixture of Al6061 and Ti powder as the foaming matrix. The effects of different Ti contents on the cell structure, cell distribution and morphology of AT-FC were focused on, and their mechanical properties under quasi-static compressive loading were investigated. The experimental results showed that different Ti contents could regulate the cell size and improve the cell morphology and distribution, in which AT-FC contains 7.5 wt% Ti had the best cell structure with an average cell size of about 1.56 mm and an average circularity of 0.82. By comparing the compressive yield strength, energy absorption and specific energy absorption of AT-FC with different Ti contents, the AT-FC with 10 wt% Ti had the best compressive yield strength of 8.96 MPa and AT-FC with 7.5 wt% Ti had the best energy absorption of 6.50 MJ/m 3 . • Preparation of low-cost, high-performance aluminium alloy foam composites by powder metallurgy. • Ti content was adjusted to obtain aluminium alloy foam composites with small and uniform cells. • Al 3 Ti can effectively improve aluminium alloy foam composites' compressive and energy-absorbing properties. [ABSTRACT FROM AUTHOR]

In this article, four new semi-auxetic structures are designed by changing the way of interface connection and adding external frames. These structures were fabricated by fused deposition modeling, which is an additive manufacturing technology. The effects of interface design and external frame on deformation mode and energy absorption performance of semi-auxetic structure under quasi-static compression are studied. It was found that the deformation modes of framed and frameless structures are different. The specific energy absorption of the semi-auxetic structure is increased by ∼52% compared with the frameless hexagonal honeycomb structure. In addition, Abaqus was used to establish finite element models of the four new semi-auxetic structures and the frameless hexagonal honeycomb structure. It can be found that the simulation results were consistent with the experimental results., Competing Interests: No competing financial interests exist., (Copyright 2023, Mary Ann Liebert, Inc., publishers.)

To improve the energy absorption performance of hexagonal thin-walled energy absorbers, a space- and weight-efficient design method is proposed by rationally arranging the distribution of the thickness along walls. The plastic deformation characteristics and energy absorption behavior of the designed non-uniform hexagonal tubes subjected to lateral compression by two rigid plates are investigated. By properly adding the thickness at the regions near side corners, the plateau forces of the designed non-uniform hexagonal tubes are higher than that of the uniform hexagonal tube. Increasing the thickness of the horizontal walls can regulate the deformation mechanism of the hexagonal tubes and thus increase the effective stroke, which means that the lateral space is apt to be fully utilized. By simultaneously increasing the thicknesses at these regions, the stroke efficiency is significantly improved and the total energy absorptions of the non-uniform tubes can be 2.0–2.3 times that of the uniform hexagonal tube. In addition, compared with the corresponding uniform hexagonal tubes with the same weight, the rationally designed non-uniform hexagonal tubes can possess dramatic improvement in comprehensive energy absorption performance: the total energy absorption, stroke efficiency, and energy absorption efficiency can be improved by nearly 40%, 22%, and 30%, respectively. [ABSTRACT FROM AUTHOR]

In this study, the energy absorption properties as well as the macroscopic and microscopic deformation behaviors of aluminum foam multilayer structures during quasi-static compression were investigated. The compression data of four types of aluminum foam structures were compared. The comparison revealed that, under quasi-static compression, the uniform-density core layer and the addition of interlayer plates were beneficial for improving the buffer and energy absorption capacity of the structures. The digital image correlation detection method was used to simulate the macroscopic deformation process of the four types of structures, and the strain field changes of the aluminum foam structure at special points of the stress–strain curve were accurately and intuitively determined. In the cell unit, the core layer deformation mainly included bending, rotation, shear, and tension. In addition, several cracks appeared in the brazing interface between the solder and the aluminum plate. An analysis revealed that the cracks were mainly caused by Al 2 O 3 during brazing and stress concentration. [ABSTRACT FROM AUTHOR]

In this paper, a novel cladding sandwich panel with aluminum foam-filled tubular cores (AFTC panel) was proposed to enhance the impact resistant performance of the traditional sandwich panel with empty tubular cores (ETC panel). The impact force and displacement responses, failure modes and energy absorption of the ETC and AFTC panels under impact loading were studied via drop-weight impact tests and numerical simulations. It was found that the impact process of the sandwich panel could be divided into three stages. In addition, the tubular cores and aluminum foam filler were found to dissipate the majority of the impact energy. The effects of impactor shape, impact position, aluminum foam filler and thickness ratio of flat steel plate to tube ( t f / t t ) on the impact behaviors of the sandwich panels were quantitatively studied. The results indicated that the impact force and energy absorption could be improved via filling aluminum foam, increasing the aluminum foam density and increasing the contact area between the impactor and sandwich panel. Filling aluminum foam could also avoid the sharp increase of the impact force after the compaction of the sandwich panel. The impact position exhibited little effect on the energy absorption of the sandwich panel when it was away from the edge of the sandwich panel. Moreover, the sandwich panel generally exhibited better energy absorption performances via specifying the flat steel plate and tubular cores to be of similar thickness. • A novel cladding sandwich panel was proposed for dissipating impact energy. • Drop-weight impact tests and FE simulations were conducted on the sandwich panel. • Failure modes and energy absorption behaviors of the sandwich panel were obtained. • The effect of variant parameters on responses of the sandwich panel was analyzed. [ABSTRACT FROM AUTHOR]

Railway vehicles are generally operated by connecting several vehicles in a row. Mechanisms connecting railway vehicles must also absorb front and rear shock loads that occur during a train's operation. To minimize damage, rail car couplers are equipped with a buffer system that absorbs the impact of energy. It is difficult to perform a crash test and evaluate performance by applying a buffer to an actual railway vehicle. In this study, a simulation technique using a mathematical buffer model was introduced to overcome these difficulties. For this, a model of each element of the buffer was built based on the experimental data for each element of the coupling buffer system and a collision simulation program was developed. The buffering characteristics of a 10-car train colliding at 25 km/h were analyzed using a developed simulator. The results of the heavy collision simulation showed that the rubber buffer was directly connected to the hydraulic shock absorber in a solid contact state, and displacement of the hydraulic buffer hardly occurred despite the increase in reaction force due to the high impact speed. Since the impact force is concentrated on the vehicle to which the collision is applied, it may be appropriate to apply a deformation tube with different characteristics depending on the vehicle location. [ABSTRACT FROM AUTHOR]

Compared with the excellent energy absorption performance under axial loading, thin-walled tubes are vulnerable to unstable global bending under oblique loading. To improve the energy absorption performance of tubes under oblique loads, a novel designed tube with hybrid cross section is studied in this paper by adding ribs at the bottom end of the tube. Quasi-static compression experiments of square (single-cell) tube, single-double hybrid tube, double-cell tube under three oblique loads were performed to verify the finite element model. Based on the verified finite element model, the energy absorption performance was compared between the single cell tube (SCT), double cell tube (DCT) and single-double hybrid tube (SDHT) under seven oblique loads. Results showed that the SDHT has the best energy absorption performance. The influence of the height, direction and number of the ribs on the energy absorption performance of the hybrid cross section tubes is also discussed in this paper. The hybrid cross-section tubes could get the best energy absorption performance when the direction and height of the ribs were appropriate. And the energy absorption performance could be further improved by increasing the number of the ribs to compose the multi-cell hybrid cross section tube. The results also showed that the multi-cell hybrid cross section tube is more stable than the traditional multi cell tube under oblique loads. This will promote the application of multi-cell tubes in vehicles. • The novelty hybrid cross section tubes are firstly proposed. • Single-double hybrid tube is found to have excellent energy absorption capacity under oblique loads. • The influence of the height and direction of the ribs is investigated and the appropriate height and direction is found for hybrid cross section tube. • The influence of the number of ribs is investigated to form the multi-cell hybrid cross section tubes. The result shows that the multi cell hybrid cross section tube can effectively reduce the sensitivity of the multi cell tube to oblique loads. [ABSTRACT FROM AUTHOR]

In this paper, the dynamic crushing responses of polyurethane foam-filled energy absorption connectors with asymmetric pleated plates were studied through drop-weight impact tests and FE simulations, from which three deformation stages were identified according to the formation and rotation of plastic hinges of asymmetric pleated plates. The effects of polyurethane foam filler as well as thickness and geometric parameter k of pleated plate on the energy absorption characteristics of connectors were analyzed quantitatively. The results indicated that filling polyurethane foam and increasing parameter k could result in higher energy absorption and specific energy absorption. In addition, thicker pleated plate could also increase energy absorption and crushing force. The results also showed that filling polyurethane foam and decreasing parameter k could reduce the peak force before densification and thus, improving crush force efficiency. Moreover, a theoretical model, considering strain rate effects of polyurethane foam and steel, was also proposed to predict energy absorption–displacement relationships of the polyurethane foam-filled connectors subjected to impact loading and its correctness was validated by comparing the calculations with experimental results. • The novel energy absorption connector with polyurethane foam and asymmetric pleated plates is proposed. • The energy absorbing connectors were tested under drop-weight impact loading. • The energy absorption performances of the proposed connectors are quantitatively evaluated. • Finite element models were established to simulate the connectors under impact loading. • The analytical model considering strain rate effects of steel and polyurethane foam was developed. [ABSTRACT FROM AUTHOR]