Hangai Yoshihiko, Yamazaki Reiji, Suzuki Takaaki
Graduate School of Science and Technology, Gunma University, Kiryu 376-8515, Japan.
Materials (Basel). 2025 Jan 17;18(2):433. doi: 10.3390/ma18020433.
The porous structure, in which many pores are intentionally placed inside the material, has excellent impact energy absorption properties. Recent studies have attempted to fabricate multi-layered porous structures with different mechanical properties within a single porous structure sample, and the mechanical properties of these structures are being elucidated. However, these studies mainly attempted to vary the densities, pore structures, and alloy compositions within a single material, such as aluminum, for the entire sample. Since multi-materials are now being promoted to utilize the most suitable material type in the right place, porous structures made of different materials, such as a combination of aluminum and resin, are expected to be required in the future. In this study, we attempted to fabricate two-layered porous structure samples of different materials by printing a resin porous structure using a 3D printer on an aluminum foam fabricated by a precursor foaming process. Static compression tests were performed on the resulting two-layered porous structure samples to investigate their mechanical properties. The resin porous structure printed by the 3D printer and the aluminum foam were both designed to expose the porous structure on the surface of the specimen so that the deformation behavior can be easily observed. The density of the resin porous structure was varied by systematically varying the filling rate of the resin porous structure to be printed, and the effect on the compression properties was investigated. The fabricated two-layered porous structure was effectively bonded between the two layers by the anchor effect, which is a mechanical bonding caused by the resin penetrating into the pores. The layers exhibited robust bonding with no evidence of separation. It was possible to fabricate a two-layered porous structure that exhibited both properties of aluminum foam and those of resin porous structure. It was found that the plateau stress in the resin porous structure layer can be controlled between about 0.5 MPa and 40 MPa, and the deformation behavior and energy absorption properties of the two-layered porous structure can be controlled by varying the resin filling rate of the resin porous structure layer. That is, it was indicated that multi-layered porous structures with various densities and consisting of various types of materials allow for the optimal design of porous structures used in structural materials.
这种多孔结构是在材料内部特意设置了许多孔隙，具有出色的冲击能量吸收性能。最近的研究试图在单个多孔结构样品中制造具有不同力学性能的多层多孔结构，并且这些结构的力学性能正在得到阐明。然而，这些研究主要尝试在整个样品中改变单一材料（如铝）内部的密度、孔隙结构和合金成分。由于现在正在推广使用多种材料以便在合适的位置使用最合适的材料类型，未来预计需要由不同材料制成的多孔结构，例如铝和树脂的组合。在本研究中，我们尝试通过使用3D打印机在通过前驱体发泡工艺制造的泡沫铝上打印树脂多孔结构来制备不同材料的两层多孔结构样品。对所得的两层多孔结构样品进行静态压缩试验以研究其力学性能。3D打印机打印的树脂多孔结构和泡沫铝都设计为在试样表面暴露多孔结构，以便能够轻松观察变形行为。通过系统地改变要打印的树脂多孔结构的填充率来改变树脂多孔结构的密度，并研究其对压缩性能的影响。制造的两层多孔结构通过锚固效应在两层之间有效地结合在一起，锚固效应是由树脂渗入孔隙引起的机械结合。各层表现出牢固的结合，没有分离的迹象。有可能制造出一种兼具泡沫铝和树脂多孔结构性能的两层多孔结构。发现树脂多孔结构层中的平台应力可以控制在约0.5MPa至40MPa之间，并且通过改变树脂多孔结构层的树脂填充率可以控制两层多孔结构的变形行为和能量吸收性能。也就是说，表明具有各种密度且由各种类型材料组成的多层多孔结构允许对用于结构材料的多孔结构进行优化设计。
