中等应变率下纸蜂窝结构的力学性能研究OA北大核心CSTPCD

Combining the laser interferometry system,using the newly developed experimental device at medium strain rates to conduct the dynamic loading experiment of paper honeycomb structure.The purpose is to study the mechanical properties of paper honeycomb structure at medium strain rates.The deformation process and dynamic failure mechanism of paper honeycomb structure were obtained by high-speed photography and digital image correlation method.Numerical methods were used to further explore the dynamic failure mechanism.The results show that the paper honeycomb structure exhibits obvious strain rate effect.The yield strength of 2.10 mm thick paper honeycomb is obviously lower than the other three sizes,showing abnormal size effect.The descending section of stress-strain curve of 2.10 mm thick paper honeycomb is also different.The main reason for it is that the failure mode of paper honeycomb structure changes with the increase of sample size.The failure mechanism of paper honeycomb structure during the loading process at medium strain rates is the change of two failure modes,namely from out-of-plane buckling to in-plane shear.The effect of cell width on mechanical properties of the structure was analyzed by numerical model.This study is a good reference significance for the optimal design of thin-walled structures.