Effect of Internal Microstructure Distribution on Quasi-Static Compression Behavior and Energy Absorption of Hollow Truss Structures.

Huilan Ren,Jianguo Ning,Haiting Shen

doi:10.3390/ma13225094

Abstract

In this work, hollow truss structures with different internal microstructure distributions, i.e., basic hollow truss structure (specimen HT), hollow truss structure with internal microstructure at joints (specimen HTSJ), and hollow truss structure with internal microstructure on tube walls (specimen HTSW), were designed and manufactured using a selective laser melting technique. The effect of internal microstructure distribution on quasi-static compressive behavior and energy absorption was investigated by experimental tests and numerical simulations. The experimental results show that compressive strength and specific compressive strength of specimen HTSW increase by nearly 50% and 14% compared to specimen HT, and its energy absorption per volume and mass also increase by 52% and 15% at a strain of 0.5, respectively. However, the parameters of specimen HTSJ exhibit limited improvement or even a decrease in different degrees in comparison to specimen HT. The numerical simulation indicates that internal microstructures change the bearing capacity and structural weaknesses of the cells, resulting in the different mechanical properties and energy absorptions of the specimens. Based on the internal microstructure design in this study, adding microstructures into the internal weaknesses of the cells parallel to the loading direction is an effective way to improve the compressive properties, energy absorption and compressive stability of hollow truss structures.

Highlights

Porous structures have a significant advantage in terms of specific stiffness/strength and specific surface area resulting in excellent energy absorption capacity, thermal management and acoustic insulation
Matrix material and relative density are important factors to determine the properties of porous structures, diverse cellular structures are the main reason why porous structures become integrated structure-function engineering materials
The first stage is the linear-elastic stage where the stress almost linearly increasing strain, andstrain, the specimen is initiallyisdeformed by elastic by buckling increases almostwith linearly with increasing and the specimen initially deformed elastic of vertical struts

Summary

Introduction

Porous structures have a significant advantage in terms of specific stiffness/strength and specific surface area resulting in excellent energy absorption capacity, thermal management and acoustic insulation. They are widely used in many engineering applications as energy absorbers, lightweight structural components, thermal transfer/shields and biological bone grafts [1,2,3,4]. It is necessary to investigate the effect of porous structure on properties. Conventional porous structures contain a large number of randomly distributed pores, and the shape, size and distribution of the pores are usually irregular. Tane et al [5]

Methods

Results

Discussion

Conclusion