【摘要】 采用纳米复合材料作为原料,通过激光烧结技术制造具有拉胀复合晶格的机械超材料。该方法为设计和制造能量吸收可调控的系统提供了技术手段。通过对材料组分和结构的优化能够高效提升复材结构的能量吸收能力。拉胀型超材料的能量吸收能力与相对密度成指数关系,约为2.5～3。经过对机械超材料进行合理的几何拓扑优化后,其具有较高的致密化强度、能量吸收能力(6.29MJ/m3)和比能量吸收能力(20.42J/g)。提出的拉胀性超材料具有接近钛合金泡沫,优于塑料泡沫、铝合金泡沫以及其他增材制造成型结构的能量吸收能力。更多还原

【Abstract】 An approach is proposed for creating 3D metamaterials of auxetic composite lattices via laser-sintering of carbon nanotubes reinforced nanocomposites, which provides a platform for the design and manufacturing of systems with programmable energy absorption capability. The optimization of constituent material and structural design enables the improvement of energy absorption performance across multiple scales. The energy absorption capacity of auxetic metamaterials is exponentially scaled with the relative density with the order of 2.5–3. The rationally topologized auxetic metamaterials exhibit a combination of high specific densification strength, ultrahigh energy absorption capacity(6.29 MJ/m3), and excellent specific energy absorption(20.42 J/g). Impressively, this group of auxetic metamaterials possesses the advantageous energy absorption capacity approaching that of titanium alloy foams as well as over a broad range of materials including plastic foams, aluminum alloy foams, and other 3D–printed lightweight structures.更多还原