弧形折纸模式薄壁结构的压缩变形与能量吸收

Compression deformation and energy absorption of thin-walled structures with arc-shaped origami patterns

选用PolyMaxTM PLA为试样材料,利用3D打印技术制备了弧形折纸薄壁管件。基于准静态轴向压缩实验,运用ABAQUS软件对弧形折纸薄壁管件轴向准静态压缩和冲击行为进行了有限元计算,探讨了其变形模式和能量吸收特性,分析了预折角和薄壁单胞管件阵列数量对其压溃模式及能量吸收的影响。有限元计算结果与实验结果吻合较好。薄壁管件的变形过程可分为4个阶段:初始压溃阶段、预折角塑性旋转阶段、腹板塑性屈曲阶段和完全压溃密实化阶段。弧形折痕的引入能够有效地降低薄壁管件在压缩过程中的初始压溃载荷峰值,减小冲击载荷的振荡幅值。对比了高度相等、质量近似相等的方管与弧形折纸薄壁管在不同冲击速度下的压缩变形与能量吸收。在准静态压缩作用下,对于单胞模型,仅有折痕倾角为70°的模型的比吸能优于方管;对于多胞管件阵列模型,方管的比吸能均优于折纸管。折纸管的压缩力效率和比总体效率均优于方管,其中折痕倾角为50°的模型的压缩力效率和比总体效率最高。在动态冲击压缩下,阵列方管的比吸能均优于阵列折纸管。当冲击速度为10 m/s时,折纸管的压缩力效率和比总体效率均优于方管,其中折痕倾角为50°的模型的压缩力效率和比总体效率最高。当冲击速度为20 m/s时,仅有折痕倾角为50°的模型的压缩力效率和比总体效率优于方管。

By chosing PolyMaxTM PLA as the sample material,thin-walled tube structures with arc-shaped origami patterns were prepared by a three-dimensional printing technology.Based on quasi-static axial compression experiments,their axial quasi-static crushing and impact compression deformation modes and energy absorption were simulated by using the ABAQUS software to investigate the influences of the prefolding angle and the number of in-plane arrays on the crushing mode and energy absorption of the structures.The results by the finite element calculation are in agreement with the experimental ones.The deformation of the tubes can be divided into four stages including initial crushing stage,prefoldingangle plastic rotation stage,web plastic buckling stage,and complete crushing and densification stage.The arc-shaped corrugations demonstrate some obvious advantages at reducing the initial peak force and the fluctuation range of the impact force.The square tube was compared with the arc-shaped origami patterns with the same height and approximately the same mass.For the single-cell models,the specific energy absorption of the model with only 70°crease inclination is higher than that of the square tube under the quasi-static crushing.For the multiple-array tube structures,the specific energy absorption of the single-cell square tube is higher than those of the arc-shaped tubes.When considering the crush force efficiency and specific total efficiency,the arc-shaped tubes have an advantage over the square tubes,the model with a crease inclination of 50°is the best.Under the impact crushing loading condition,the specific energy absorptions of the multiple-array tubes are higher than those of the arc-shaped tubes.The crush force efficiency and specific total efficiency of the arc-shaped tubes are higher than those of the square tubes under the impact velocity of 10 m/s,the model with a crease inclination of 50°is the highest.The crush force efficiency and specific total efficiency of the model with only 50°crease inclination are higher than those of the square tube under the impact velocity of 20 m/s.