Modern additive manufacturing technologies allow the creation of parts characterized by complex geometries that cannot be created using conventional production techniques. Among them the Selective Laser Melting (SLM) technique is very promising. By using SLM it is possible to create lightweight lattice structures that may fill void regions or partially replace bulk regions of a given mechanical component. As a consequence, the overall mechanical properties of the final component can be greatly enhanced, such as the resistance to weight ratio and its damping capacity against undesired vibrations and acoustic noise. Nevertheless, only a few research works focused on the characterization of the dynamic behavior of lattice structures, that were mainly investigated in the low frequency range or directly tested on some specific applications. In this work the dynamic behavior of lattice structures in the medium-high frequency range was experimentally investigated and then modelled. For this purpose, different types of lattice structures made of AlSi10Mg and AISI 316L were measured. Experimental modal analysis was performed on the obtained specimens in order to assess the influence of lattice material and unit cell geometry on their global dynamic behavior. Experimental results revealed that lattice structures have superior damping characteristics compared to solid materials having an equivalent static stiffness. Eventually, the classic Rayleigh model was found to be adequate - with some approximation - to explain the damping behavior of a generic lattice structure.

现代增材制造技术可以创建具有复杂几何形状的零件，而这些零件是使用常规生产技术无法创建的。其中选择性激光熔化（SLM）技术非常有前途。通过使用SLM，可以创建轻质的晶格结构，该结构可以填充给定机械组件的空隙区域或部分替换体积较大的区域。结果，可以极大地提高最终部件的整体机械性能，例如抗重量比及其对不希望的振动和声音的阻尼能力。然而，只有很少的研究工作专注于晶格结构的动态行为的表征，这些研究主要在低频范围内进行研究，或者在某些特定应用中直接进行测试。在这项工作中，对中高频范围内晶格结构的动力学行为进行了实验研究，然后进行了建模。为此，测量了由AlSi10Mg和AISI 316L制成的不同类型的晶格结构。为了评估晶格材料和晶胞几何形状对其整体动态行为的影响，对获得的标本进行了实验模态分析。实验结果表明，与具有相同静态刚度的固体材料相比，晶格结构具有出色的阻尼特性。最终，经典的瑞利模型被发现是适当的（有些近似）足以解释通用晶格结构的阻尼行为。