支柱弯曲对开孔泡沫铝力学性能影响的理论分析与数值模拟

摘要

Firstly,a theoretical method was employed to analyze the effect of the curvature of struts on the stiff-ness and strength properties of the open cell foam,based on the assumption that all the struts were curved.Then theoretical formulas were obtained for the prediction of the Young’s modulus and yield strength of these foam con-taining curved struts.The validity of the theoretical prediction was verified by comparing with the simulation results of the finite element method.Finally,the finite element model was employed to investigate the effects of the content of curved struts,the curvature,and the anisotropy ratio on the compressive properties of the aluminum foam.The results indicate that the curvature of struts has a greater influence on the elastic modulus than the plastic collapse strength.The compressive properties of the aluminum foam show strong dependence on the curvature of struts,the content of curved struts,and the anisotropy ratio of cell structure.%首先根据实际泡沫材料中存在不少弯曲支柱，且形状接近于弧线，在假设全部支柱为弯曲支柱的情况下，利用理论方法分析了支柱弯曲对开孔泡沫材料刚度和强度性能的影响规律，得到了理论预测含弯曲支柱开孔泡沫材料杨氏模量和屈服强度的公式。然后，通过有限元模拟方法验证了上述理论预测模型的有效性。最后，利用有限元模型研究了不同比例的弯曲支柱、不同弧度的弯曲支柱和不同各向异性比对泡沫铝压缩力学行为的影响。结果表明，弯曲支柱对弹性模量的影响比对塑性坍塌强度的影响大；而弯曲支柱对泡沫铝压缩力学行为的影响则与支柱的弧度、支柱含量和胞体结构的各向异性比有关。