摘要
具有高强度和高能量吸收能力的轻质夹芯结构在机械领域具有至关重要的应用.提出了一种基于SLM(激光选区熔化)技术的弹性阻尼单元结构,该结构在受载时可以产生较大的弹性变形,从而在弹性变形阶段吸收大量的能量.根据SLM工艺特征,设计了弹性阻尼单元的结构和布局,并研究了其可制造约束条件.最后,采用SLM技术加工了三组具有不同结构参数的弹性阻尼单元和与其具有相同高度的Kagome结构,并进行了压缩试验.根据试验结果分析了单元结构参数对其承载性能和能量吸收能力的影响,并对比了弹性阻尼单元和Kagome结构性能的差异.试验结果表明,弹性阻尼单元强度和能量吸收能力优于Kagome结构.且参数为a=2.2 mm,m=3.1 mm,n=4.6 mm弹性阻尼单元,在相同的质量下,强度比Kagome结构高约36.11%,在破坏时吸收能量比Kagome结构高约26.83%,弹性变形时吸收能量比Kagome结构高约39.1%.
Lightweight sandwich structures with high strength and high energy absorption ability are of paramount importance in the mechanical field. An elastic damping unit structure based on SLM(laser selective melting) technology is proposed, which can generate large elastic deformation when loaded, so that a large amount of energy is absorbed in the elastic deformation stage. According to the characteristics of SLM process, the structure and layout of the elastic damping unit are designed, and the manufacturability constraints are studied. Finally, three sets of elastic damping units with different structural parameters and the Kagome structure with the same height were processed by SLM technology, and the compression test was carried out. According to the test results, the influence of unit structure parameters on its bearing capacity and energy absorption capacity was analyzed, and the difference of elastic damping unit and Kagome structure performance was compared. The test results show that the strength and energy absorption capacity of elastic damping unit are better than Kagome, and when the parameters are a=2.2 mm, m=3.1 mm, n=4.6 mm, at the same weight, the strength of the elastic damping unit is about 36.11% higher than that of the Kagome structure, the energy absorbed at the time of failure is about 26.83% higher than that of the Kagome structure, and the energy absorbed during elastic deformation is about 39.1% higher than that of the Kagome structure.
引文
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