多胞管增强泡沫铝复合结构的压缩和吸能性能研究

Compression and energy absorbing properties of multi-cell tube reinforced aluminum foam

针对泡沫铝强度较低、吸能性能弱的问题,提出了一种有效的增强办法:将金属多胞管填充至泡沫铝中,并用环氧胶固定,制备出新型多胞管增强泡沫铝复合结构(MTRF)。通过实验和商业有限元软件ABAQUS/explicit研究了该类复合结构的压缩和吸能性能。实验结果表明:与常规泡沫铝相比,多胞管增强泡沫铝复合结构的抗压强度和单位质量吸能性能分别提升了500%和700%,显示了MTRF结构优越的承载能力和能量吸收性能。同时,实验结果验证了有限元模型的准确性。在此基础上数值研究了MTRF的增强机理,结果表明:泡沫铝为多胞管提供了强的侧向支撑,抑制了其在压缩载荷作用下横向变形,使得变形模式由低阶变形模式向高阶的变形模式转变,即表现为塑性铰数目增多,使得MTRF结构承载和吸能性能显著提高。

Aiming at low strength and weak energy absorption of aluminum foam,this paper proposes an effective method to enhance aluminum foam:filling metallic multicellular tube into pre-perforated aluminum foam and fixing it with epoxy resin to prepare a new multi-cell tube reinforced aluminum foam composite structure(MTRF).The compression and energy absorption properties of the composite structure were studied by experiment and commercial finite element software ABAQUS/explicit.The experimental results show that compared with those of aluminum foam,the compressive strength and unit mass energy absorption performance of multi-cell tube reinforced aluminum foam structure are increased by 500%and 700%,respectively,indicating the excellent load carrying capacity and energy absorption performance of MTRF structure.Meanwhile,the experimental results verify the accuracy of the finite element model.Based on this,the enhancement mechanism of MTRF is studied by Abaqus/Explicit.The numerical results show that the foam aluminum provides enough lateral support for the multi-cell tube,restraining its lateral deformation under compression load,and makes the deformation mode change from the low order deformation mode to the higher order deformation mode.That is,the number of plastic hinge increases,resulting in a significant increase in the carrying capacity and energy absorption of the MTRF.