• International Journal of Automotive Technology
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• v.4 no.3
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• pp.141-147
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• 2003

For improving high-safety, convenience, and ride comfort, the automotive design suffers from radical increase of the weight, the recycling-related rules, regulations on the waste gas, and environmental protection of the resources. Among them, it is well known that the weight increase is the most critical. Thus, in order to minimize the weight of the body-in-white that takes up 20-30% of the whole weight of the automobile, most automotive manufacturers have attempted to develop the aluminum intensive body-in-white using aluminum space frames. In this research, the crush test and simulation for aluminum extrusions are performed to evaluate the collapse characteristics of that light weighted material. Also. the same test and simulation was done for aluminum extrusions filled with structural foam. Then, these results are analyzed and compared. From these studies, the effectiveness of structural foam is evaluated in improving automotive crashworthiness. Finally, the design strategy and guideline of the structural form are suggested in order to improve the crashworthiness for aluminum space frame in the vehicle.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.4
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• pp.496-503
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• 2003

An experimental study has been performed on thermal transport from an aluminum foam heat sink under a confined impinging air jet. Three kinds of aluminum foam heat sinks with 10, 20 and 40 PPI and a conventional pin-fin heat sink are tested in the present study. The jet Reynolds number is varied in the range of Re=667～5672 The effect of the confinement disk diameter and the distance between the confinement disk and the heater surface on the averaged Nusselt number is investigated in detail. The results are also compared with those of the unconfined impinging air jet. The critical distance, at which thermal performance shows a minimum compared to the unconfined jet impinging, will be described in terms of the Reynolds number and the pore density of the aluminum foam.

• Steel and Composite Structures
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• v.39 no.3
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• pp.229-241
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• 2021

This work focused on aluminum foam sandwich (AFS) with different foam core densities and different face-sheet thicknesses subjected to constant amplitude three-point bending cyclic loading to study its fatigue performance. The experiments were conducted out by a high frequency fatigue test machine named GPS-100. The experimental results showed that the fatigue life of AFS decreased with the increasing loading level and the structure was sensitive to cyclic loading, especially when the loading level was under 20%. S-N curves of nine groups of AFS specimens were obtained and the fatigue life of AFS followed three-parameter lognormal distribution well. AFS under low cyclic loading showed pronounced cyclic hardening and the static strength after fatigue test increased. For the same loading level, effects of foam core density and face-sheet thickness on the fatigue life of AFS structure were trade-off and for the same loading value, the fatigue life of AFS increased with aluminum foam core density or face-sheet thickness monotonously. Core shear was the main failure mode in the present study.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.396-402
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• 2000

Porous structures of aluminum foam have been studied. The apparent foam shape, foam hight, density, pore size, shape, and their distributions in various section areas of the experimental samples have been investigated. The sample have been cast into metallic mold, using aluminum foam prepared from a precursor based on pure Al ingot mixed with various amount of 1-2wt% increasing viscosity and foam agent materials. The process provides for flexibility in design of foam structures via relatively easy control over the amount of hydrogen evolution and the drainage processes which occur during foam formation. This is facilitated by manupulating parameters such as the foaming agent, thermal histories during solidification and mix melt viscosities. The acoustical performance of the panel made with the foamed aluminum is considerably improved; its absorption coefficient shows NRC 0.6-0.8. It has been found that the Al foam is very preferable for the compactness of the thermal system.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.198-201
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• 2001

Porous structures of aluminum foam have been studied by using return aluminum scrap. The apparent foam shape, foam height, density, pore size and their distributions in various section areas of the experimental samples have been investigated. The sample have been cast into metallic mold, using aluminum foam prepared from a precursor based on pure Al ingot and return aluminum scrap mixed with various amounts of 1-2wt% increasing viscosity and foam agent materials. The process provides for flexibility in design of foam structures via relatively easy control over the amount of hydrogen evolution and the drainage processes which occur during foam formation. This is facilitated by manipulating parameters such as the foaming agent, thermal histories during solidification and mix melt viscosities. A metal for producing the foamed are decomposing a foaming agent in a molten metal such that there is an initial and a subsequent expansion due to foaming agent. It has been found that the Al porous foaming with variation amount of 1∼2wt% foam agent and at 2min holding time, which melting temperature has appeared homogeneous pore size at 650∼700$^{\circ}C$. The compression strength were 10-13 kg/min at 125ppi, and increased by higher pore density. The acoustical performance of the panel made with the foamed aluminum is considerably improved; its absorption coefficient shows NRC 0.6-0.8. It has been found that the Al foam is very preferable for the compactness of the thermal system.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.19-24
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• 2003

Potential applications of foam-filled section are the automotive structures. A foam-filled section can be used for the front rail and firewall structures to absorb impact energy during frontal or side collision. In the case of side collision where bending is involved in the crushing mechanics, the foam filler will be significant in maintaining progressive crushing of the thin-walled structures so that more impact energy can be absorbed. In this study, the manufacturing process of closed cell aluminum alloy foam filled stainless steel tube was studied, and the various foam filled specimens including piecewise fillers were prepared, tested and discussed about the bending behaviors.

• Journal of the Korea Convergence Society
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• v.2 no.3
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• pp.1-6
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• 2011

Aluminum foam is one of the representative light-weight materials. In this study we analyzed the mechanical properties of the aluminum foam structures. Aluminum materials with pores have novel mechanical characteristics such as flame retardancy, damping, and energy absorption which are superior to those of polymer foam. Furthermore its reusable properties draw considerable interests. General properties, energy and acoustic absorption will be investigated and future research issues such as binding techniques of foam materials with other structures will be discussed through foam application examples.

• Journal of Korea Foundry Society
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• v.27 no.2
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• pp.83-87
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• 2007

Aluminum plates of the same materials as the foam were attached by the casting process inserting the foam as a core to investigate the tensile property of open cell foams. Tensile properties of the open cell 6063 aluminum alloy foam of $10{\sim}30$ PPI were measured before and after heat treatment. Densities of test specimens were between 0.14 and $0.29g/cm^3$. Tensile strength of the 6063 aluminum foam after heat treatment showed little change. C values were in the range of $0.41{\sim}0.87$ for as cast foams and $0.11{\sim}0.27$ for T6 heat treated foams in the eq. of ${\sigma}^* _{pl}/{\sigma}_{ys}=C({\rho}/{\rho}_s)^{1.5}$, and increased with increase in the cell size.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.9
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• pp.3802-3807
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• 2011

In this study, in-plane and out-plane compression tests of aluminum foam and honeycomb sandwich composites were carried out. Through these tests, the relationships of load-displacements were analyzed and the compression characteristics were compared with each other. The specimens were compressed with the speed of 1mm/min by using the universal testing machine. Experimental procedures were taken with photograph by the camera and load cell data were stored into computer. Test results showed that buckling was occurred at the aluminum foam core and honeycomb core according to the increase of load. In the in-plane compression test, the maximum load of aluminum foam specimen was similar with that of honeycomb sandwich. The property of honeycomb was better than that of the foam in consideration of specific gravity. In the out-plane compression test, compression maximum load of aluminum honeycomb sandwich composite was higher than that of aluminum foam sandwich composite.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.478-484
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• 2012

In this study, compression analyses of sandwich composites with porous core were carried out. Finite element models of aluminum foam and honeycomb core sandwich composite material were applied solid element. In the case of aluminum foam core, valid equivalence damage model was applied. In the in-plane compression analysis, the maximum load of aluminum foam core sandwich was similar with that of aluminum honeycomb core sandwich. But in case of aluminum honeycomb core sandwich, the load support region becomes longer in comparison with aluminum foam core sandwich. In the out-plane compression analysis, compression maximum load of aluminum honeycomb core sandwich was higher than that of aluminum foam core sandwich. Through these Simulation analysis, obtains the behavior of sandwich composites.