动态异面压缩下铝蜂窝平均坍塌应力分析与试验验证

Analysis and Experimental Verification of Mean Crushing Stress of Aluminum Honeycombs under Dynamic Out-of-Plane Compression

为研究铝蜂窝在动态异面压缩下的平均塑性坍塌应力,在铝蜂窝准静态压缩的理论研究基础上,考虑铝蜂窝应变率效应对材料力学性能的影响,采用Cowper-Symonds模型,以基本折叠单元为研究对象,采用等效周长方法求取应变率,给出了两个动态异面压缩下铝蜂窝平均塑性坍塌应力的理论计算公式。落锤冲击试验结果与仿真结果显示,Tresca屈服准则下的动态平均塑性坍塌应力与试验及仿真结果的相关系数均在98%以上,验证了理论推导的正确性。本文给出的理论计算公式对研究动态冲击下铝蜂窝的异面压缩性能具有一定的工程指导意义。

In order to study the mean plastic crushing stress of aluminum honeycombs under dynamic out-of-plane compression,based on the theoretical study on quasi-static compression of aluminum honeycombs,the influence of the aluminum honeycomb strain rate effect on the mechanical properties of the material is considered.Using the Cowper-Symonds model and taking the basic folding element as the research object,the equivalent perimeter method is used to obtain the strain rate.Two theoretical calculation formulae of the mean plastic crushing stress of aluminum honeycombs under dynamic out-of-plane compression are given.The drop hammer impact test results and simulation results show that the correlation coefficient between the dynamic mean plastic crushing stress under the Tresca yield criterion and the experimental stress or simulation stress is above 98%,which verifies the correctness of the theoretical derivation.The theoretical calculation formulae given in this paper have certain engineering guiding significance for studying the out-of-plane compression performance of aluminum honeycombs under dynamic impact.