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L. Xia - One of the best experts on this subject based on the ideXlab platform.
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Achieving high Energy Absorption capacity in cellular bulk metallic glasses.
Scientific reports, 2015Co-Authors: Shunhua Chen, K C Chan, L. XiaAbstract:Cellular bulk metallic glasses (BMGs) have exhibited excellent Energy-Absorption performance by inheriting superior strength from the parent BMGs. However, how to achieve high Energy Absorption capacity in cellular BMGs is vital but mysterious. In this work, using step-by-step observations of the deformation evolution of a series of cellular BMGs, the underlying mechanisms for the remarkable Energy Absorption capacity have been investigated by studying two influencing key factors: the peak stress and the decay of the peak stress during the plastic-flow plateau stages. An analytical model of the peak stress has been proposed and the predicted results agree well with the experimental data. The decay of the peak stress has been attributed to the geometry change of the macroscopic cells, the formation of shear bands in the middle of the struts and the “work-softening” nature of BMGs. The influencing factors such as the effect of the strut thickness and the number of unit cells have also been investigated and discussed. Strategies for achieving higher Energy Absorption capacity in cellular BMGs have been proposed.
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Pronounced Energy Absorption capacity of cellular bulk metallic glasses
Applied Physics Letters, 2015Co-Authors: S.-h. Chen, F F Wu, K C Chan, L. XiaAbstract:Cellular bulk metallic glasses (BMGs) with macroscopic cellular structures were designed and fabricated. The cellular BMGs exhibited remarkable Energy Absorption capacity as compared with reported BMG foams and honeycombs. The enhanced Energy Absorption capability is attributed to the large plastic bending of the struts, the blunting of the cracks, and the large plastic deformation at the nodes. This work shows that, in cellular BMGs, the macroscopic cellular structures are more efficient in dissipating mechanical Energy than microscopic cellular structures, opening a window for developing Energy Absorption devices using BMGs.
Hiroyuki Hamada - One of the best experts on this subject based on the ideXlab platform.
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A study on the Energy Absorption capacity of braided rod composites
Composite Structures, 2018Co-Authors: Yuqiu Yang, Khalil Ahmed, Ruiyun Zhang, Ruohua Liu, Gabriel Y. Fortin, Hiroyuki HamadaAbstract:Abstract Composite materials are becoming popular among automobile manufacturers because of their high strength, light weight, and controlled crushing mechanisms. Many composite structures have been designed and developed as Energy Absorption components in automobiles until now. Following the trend, in this study UD and braided UD glass fiber rods were manufactured as an Energy Absorption component for the automotive industry and their Energy Absorption capability was measured by quasi-static compression testing. In order to fully understand the crushing mechanisms, the effect of braiding layers, braiding technique, taper angle, single and multiple rods and their separation on the Energy Absorption capability was investigated. Braided UD rods absorbed more Energy compared to the MFW (multifilament wounded) rods, while tapering one side of the rod greatly influenced the crushing distance, yield point, and load bearing capabilities. Additionally, the mean load of three BR-1L rods was almost three times higher than that of a single rod however, it was influenced by varying the distance among them. The aim of this research was to collect more data about the crashworthiness of composite rods under different parameters and to gain a better understanding for future research work.
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Energy Absorption capability of multi axial warp knitted frp tubes
International Journal of Crashworthiness, 2009Co-Authors: Yaling Yang, Asami Nakai, Satoshi Sugihara, Hiroyuki HamadaAbstract:With fibre-reinforced plastics (FRPs) being adopted widely in many fields, low manufacturing cost with high mechanical property is urgently required. Unfortunately, traditional composite structures and manufacturing methods are very labour-intensive and not cost-effective for wide commercial applications. Therefore, multi-axial warp knitting (MWK) is attractive as a new reinforcement form in composite structures because it incorporates textile structural property and the automated pultrusion process. Additionally, this fabric, made by connecting several fibre layers by stitching yarns, is considered to enhance the property through the thickness, which also raises questions as to its effect on Energy Absorption. In this study, several forms of glass and carbon MWK FRP tubes fabricated by pultrusion process, which have circular or square cross-section geometries, were axially crushed by quasi-static, high compressive speed or impact crash tests to determine the Energy-Absorption capabilities. It is found that the Energy-management capacities of FRP tubes involved in different MWK fabrics are different both in the typical load/displacement response and in terms of specific Energy Absorption. The cross sections were observed microscopically to clarify the effect of the constitution and the position of MWK fabric.
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Energy Absorption of braiding pultrusion process composite rods
Composite Structures, 2002Co-Authors: Hiroshi Saito, E C Chirwa, Ryuji Inai, Hiroyuki HamadaAbstract:Abstract Composite body structures are now commonly used in road and rail vehicles, ships and submarines, aircraft and spacecraft due to their capability to effectively absorb high kinetic Energy to weight ratio. One such structure designed as an Energy device with pre-determined properties is a braided pultruded process (BPP) composite rod of either circular or square cross-section. This paper reports the results of an investigation on circular BPP rods and unidirectional pultruded process rods in epoxy matrix subjected to compressive loading. Test results depict BPP rods to have superior properties in comparison to the unidirectional rods in terms of Energy Absorption capability that is manifested through well-defined progressive crushing failure mechanisms. Generally the rods' fracture and complete failure mechanisms show distinct creation of buckling zone, followed by generation of fronds as the wedge area increases with every augmentation of applied load. Fracture morphology related to overall performance characteristics is discussed through the step-by-step analysis of microphotography. The specific Energy Absorption property is shown to be best achieved in carbon/carbon (C/C) BPP followed by glass/carbon (G/C) rod combination and then the glass/glass (G/G) BPP rods. The latter (G/G), although worst performer of all the rods in terms of Energy characteristics, still outperforms the documented best tubes made of Kevlar fibres, steel and aluminium. On average, the carbon/carbon (C/C) BPP rod's specific Energy Absorption is between 35% and 55% more than the nearest comparable tubes.
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effect of fiber orientation on the Energy Absorption capability of carbon fiber peek composite tubes
Journal of Composite Materials, 1996Co-Authors: Hiroyuki Hamada, S. Ramakrishna, H SatoAbstract:Previous research works identified the effects of cooling rate, testing speed and tube geometry on the Energy Absorption behavior of carbon fiber reinforced polyether-ether-ketone (carbon/PEEK) composite tubes. One of the objectives of this work is to optimize the Energy Absorption capability of these tubes by changing the fiber orientation. Composite tubes with fiber orientations 0°, ±5°, ±10°, ±15°, ±20°, ±25° and ±30° with respect to the axis of the tube have been investigated. The Energy Absorption capability as well as the crush zone morphology were dependent on the fiber orientation. Efforts have been made to relate the variations of specific Energy to the changes in the crush zone morphology. Tubes with ±15° fiber orientation displayed a specific Energy of 225 kJ/kg, the highest ever reported in the literature. The fracture mechanisms that resulted in the superior Energy Absorption performance of these tubes have been identified.
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Energy Absorption behavior of carbon fiber reinforced thermoplastic composite tubes
Journal of Thermoplastic Composite Materials, 1995Co-Authors: Hiroyuki Hamada, Zenichiro Maekawa, H SatoAbstract:The primary objective of this work was to study the Energy Absorption characteristics of carbon-fiber-reinforced thermoplastic composite tubes. Composite tubes with different thermoplastic matrices...
S Ramesh - One of the best experts on this subject based on the ideXlab platform.
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advanced composite sandwich structure design for Energy Absorption applications blast protection and crashworthiness
Composites Part B-engineering, 2012Co-Authors: Faris Tarlochan, S Ramesh, S HarpreetAbstract:Abstract This paper describes an experimental investigation on the response of composite sandwich structures with tubular inserts to quasi-static compression. The performance parameters, namely the peak load, absorbed crash Energy, specific Energy Absorption; average crushing load and crush force efficiency were evaluated. The composite sandwich specimens were fabricated from glass fiber, polystyrene foam and epoxy resin. The primary mode of failure observed was progressive crushing with the composites exhibiting high Energy Absorption capabilities and high crushes force efficiency. The mechanism of progressive crushing of the sandwich structures and its relation to the Energy Absorption capabilities was deliberated. Furthermore, a statistical analysis was performed to investigate the effects of the design variables and also to determine if there were interactions between these variables. Such information is vital in the design of polymer composite sandwich structures as Energy absorbers.
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composite sandwich structures with nested inserts for Energy Absorption application
Composite Structures, 2012Co-Authors: Faris Tarlochan, S RameshAbstract:Abstract Polymer composite sandwich structures are promising candidate structures for reducing vehicle mass, thereby improving the fuel economics. Nonetheless, to fully explore this material as the primary structure and Energy absorber in vehicles, it is important to understand the Energy Absorption capability of this material. Hence, in the present work, comprehensive experimental investigation on the response of composite sandwich structures to quasi-static compression has been carried out. The crashworthiness parameters, namely the peak force, absorbed crash Energy, specific absorbed Energy, average crushing force and crush force efficiency of various types of composite sandwich structures were investigated in a series of edgewise axial compression tests. The tested composite sandwich specimens were fabricated from glass and carbon fiber with epoxy resin. Four distinct modes of failure were observed and recorded. The primary mode of failure observed was progressive crushing with high Energy Absorption capability. The optimized design in this study had a specific Energy Absorption capability of 47.1 kJ/kg with a good crush force efficiency of 0.77, higher than conventional metals.
Faris Tarlochan - One of the best experts on this subject based on the ideXlab platform.
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advanced composite sandwich structure design for Energy Absorption applications blast protection and crashworthiness
Composites Part B-engineering, 2012Co-Authors: Faris Tarlochan, S Ramesh, S HarpreetAbstract:Abstract This paper describes an experimental investigation on the response of composite sandwich structures with tubular inserts to quasi-static compression. The performance parameters, namely the peak load, absorbed crash Energy, specific Energy Absorption; average crushing load and crush force efficiency were evaluated. The composite sandwich specimens were fabricated from glass fiber, polystyrene foam and epoxy resin. The primary mode of failure observed was progressive crushing with the composites exhibiting high Energy Absorption capabilities and high crushes force efficiency. The mechanism of progressive crushing of the sandwich structures and its relation to the Energy Absorption capabilities was deliberated. Furthermore, a statistical analysis was performed to investigate the effects of the design variables and also to determine if there were interactions between these variables. Such information is vital in the design of polymer composite sandwich structures as Energy absorbers.
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composite sandwich structures with nested inserts for Energy Absorption application
Composite Structures, 2012Co-Authors: Faris Tarlochan, S RameshAbstract:Abstract Polymer composite sandwich structures are promising candidate structures for reducing vehicle mass, thereby improving the fuel economics. Nonetheless, to fully explore this material as the primary structure and Energy absorber in vehicles, it is important to understand the Energy Absorption capability of this material. Hence, in the present work, comprehensive experimental investigation on the response of composite sandwich structures to quasi-static compression has been carried out. The crashworthiness parameters, namely the peak force, absorbed crash Energy, specific absorbed Energy, average crushing force and crush force efficiency of various types of composite sandwich structures were investigated in a series of edgewise axial compression tests. The tested composite sandwich specimens were fabricated from glass and carbon fiber with epoxy resin. Four distinct modes of failure were observed and recorded. The primary mode of failure observed was progressive crushing with high Energy Absorption capability. The optimized design in this study had a specific Energy Absorption capability of 47.1 kJ/kg with a good crush force efficiency of 0.77, higher than conventional metals.
K C Chan - One of the best experts on this subject based on the ideXlab platform.
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Achieving high Energy Absorption capacity in cellular bulk metallic glasses.
Scientific reports, 2015Co-Authors: Shunhua Chen, K C Chan, L. XiaAbstract:Cellular bulk metallic glasses (BMGs) have exhibited excellent Energy-Absorption performance by inheriting superior strength from the parent BMGs. However, how to achieve high Energy Absorption capacity in cellular BMGs is vital but mysterious. In this work, using step-by-step observations of the deformation evolution of a series of cellular BMGs, the underlying mechanisms for the remarkable Energy Absorption capacity have been investigated by studying two influencing key factors: the peak stress and the decay of the peak stress during the plastic-flow plateau stages. An analytical model of the peak stress has been proposed and the predicted results agree well with the experimental data. The decay of the peak stress has been attributed to the geometry change of the macroscopic cells, the formation of shear bands in the middle of the struts and the “work-softening” nature of BMGs. The influencing factors such as the effect of the strut thickness and the number of unit cells have also been investigated and discussed. Strategies for achieving higher Energy Absorption capacity in cellular BMGs have been proposed.
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Pronounced Energy Absorption capacity of cellular bulk metallic glasses
Applied Physics Letters, 2015Co-Authors: S.-h. Chen, F F Wu, K C Chan, L. XiaAbstract:Cellular bulk metallic glasses (BMGs) with macroscopic cellular structures were designed and fabricated. The cellular BMGs exhibited remarkable Energy Absorption capacity as compared with reported BMG foams and honeycombs. The enhanced Energy Absorption capability is attributed to the large plastic bending of the struts, the blunting of the cracks, and the large plastic deformation at the nodes. This work shows that, in cellular BMGs, the macroscopic cellular structures are more efficient in dissipating mechanical Energy than microscopic cellular structures, opening a window for developing Energy Absorption devices using BMGs.