Nano-deposition on 3-D open-cell aluminum foam materials for improved energy absorption capacity
Nano-deposition on 3-D open-cell aluminum foam materials for improved energy absorption capacity
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DOI：
10.1016/j.msea.2013.02.032
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发表时间：
2013-06
期刊：
影响因子：
6.4
通讯作者：
W. Wang;R. Burgueño;Jung‐Wuk Hong;I. Lee
中科院分区：
文献类型：
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作者：
W. Wang;R. Burgueño;Jung‐Wuk Hong;I. Lee
几十年来，开孔泡沫铝(Al)一直被用作吸能器。它们的能量吸收能力可以通过增加泡沫支柱的厚度或增加泡沫的相对密度来增强。然而，由于其应力-应变特性关系的固有特性，在均质支柱加厚时，不能在不降低致密应变的情况下实现平台应力的增加。在本工作中，为了克服这一固有的障碍，在泡沫铝上沉积了纳米晶铜，首次制备了新型的三维铜/铝、异质增厚的复合泡沫结构材料。建立了无氰化纳米晶铜电沉积体系，研究了泡沫铝的吸能能力与泡沫孔尺寸和铜层厚度的关系。多种表征手段证实了铜沉积的纳米晶结构(38 Nm)。经60μm铜涂层增强的泡沫铝(平均支柱厚度为192μm)的吸能能力是普通泡沫铝的3倍。复合材料的压缩应力-应变响应表明，由于泡沫支柱厚度和孔径的微小变化，致密化应变与未涂层泡沫相比没有显着降低。在相同的总支撑厚度(即相同的有效体积密度和孔隙率)下，对薄的铜包覆和未包覆的泡沫铝样品的比较表明，纳米增强的泡沫铝具有比相同总厚度的普通泡沫铝更好的能量吸收能力(∼大2倍)。
Open cell aluminum (Al) foams have been used as energy absorbers for decades. Their energy absorption capacity can be enhanced by thickening the foam struts, or increasing the foam's relative density. However, the enhancement is compromised by the inherent characteristics of its stress–strain property relationship, whereby upon homogeneous strut thickening, an increase in the plateau stress without a reduction in densification strain cannot be achieved. In this work, to overcome this inherent barrier, nano-crystalline copper (Cu) was deposited onto the Al foam and novel 3-D Cu/Al, heterogeneously thickened, composite foam structured materials were fabricated and tested for the first time. A non-cyanide nano-crystalline copper electro-deposition system was setup for the coating of open-cell Al foam, and, the energy absorption capacity as a function of foam pore size and Cu coating thickness was investigated. A variety of characterization methods confirmed the nano-crystalline structure of the Cu deposition (38nm). The energy absorption capacity of Al foams (with average strut thickness of 192μm) reinforced with a 60μm Cu coating was 3 times greater than that of plain foams. The compressive stress–strain response of the composite samples showed no significant reduction of the densification strain compared to the uncoated foams due to the small change in the foam strut thickness and pore size. A comparison between thin Cu-coated and uncoated Al foam samples with the same overall strut thickness (i.e., same effective volume density and porosity) showed that the nano-reinforced foams had superior energy absorption capacity over plain foams with the same overall thickness, (∼2 times greater).