Andersen Olaf, Vesenjak Matej, Fiedler Thomas, Jehring Ulrike, Krstulović-Opara Lovre
Fraunhofer Institute for Manufacturing Technology and Advanced Materials, Branch Lab Dresden, D-01277 Dresden, Germany.
Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia.
Materials (Basel). 2016 May 21;9(5):398. doi: 10.3390/ma9050398.
Rigid metallic fiber structures made from a variety of different metals and alloys have been investigated mainly with regard to their functional properties such as heat transfer, pressure drop, or filtration characteristics. With the recent advent of aluminum and magnesium-based fiber structures, the application of such structures in light-weight crash absorbers has become conceivable. The present paper therefore elucidates the mechanical behavior of rigid sintered fiber structures under quasi-static and dynamic loading. Special attention is paid to the strongly anisotropic properties observed for different directions of loading in relation to the main fiber orientation. Basically, the structures show an orthotropic behavior; however, a finite thickness of the fiber slabs results in moderate deviations from a purely orthotropic behavior. The morphology of the tested specimens is examined by computed tomography, and experimental results for different directions of loading as well as different relative densities are presented. Numerical calculations were carried out using real structural data derived from the computed tomography data. Depending on the direction of loading, the fiber structures show a distinctively different deformation behavior both experimentally and numerically. Based on these results, the prevalent modes of deformation are discussed and a first comparison with an established polymer foam and an assessment of the applicability of aluminum fiber structures in crash protection devices is attempted.
由多种不同金属和合金制成的刚性金属纤维结构，主要针对其诸如热传递、压降或过滤特性等功能特性进行了研究。随着基于铝和镁的纤维结构的近期出现，此类结构在轻质防撞装置中的应用已成为可能。因此，本文阐述了刚性烧结纤维结构在准静态和动态载荷下的力学行为。特别关注了相对于主要纤维取向在不同加载方向上观察到的强烈各向异性特性。基本上，这些结构表现出正交各向异性行为；然而，纤维板的有限厚度导致与纯正交各向异性行为存在适度偏差。通过计算机断层扫描检查测试样本的形态，并给出不同加载方向以及不同相对密度的实验结果。使用从计算机断层扫描数据得出的实际结构数据进行了数值计算。根据加载方向，纤维结构在实验和数值上均表现出明显不同的变形行为。基于这些结果，讨论了普遍的变形模式，并尝试与已有的聚合物泡沫进行首次比较以及评估铝纤维结构在防撞装置中的适用性。
