Collapse Behavior and Energy Absorbing Characteristics of 3D-Printed Tubes with Different Infill Pattern Structures: An Experimental Study

This work investigates the impact of infill pattern structure on the crashworthy performance and deformation history of 3D-printed tubes subjected to a quasi-static axial compression load. The proposed tubes were made from polylactic acid (PLA) using a 3D printing technique. Five infill pattern structures were adapted, i.e. circular, square, triangle, zigzag and cross patterns with 50% infill density. The crashworthy analysis was carried out by assessing different indicators, i.e. peak force (Fip)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathrm{F}}_{\mathrm{ip}})$$\end{document}, mean crush force (Fm)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathrm{F}}_{\mathrm{m}})$$\end{document}, total absorbed energy (U), specific absorbed energy (SEA), and crushing force efficiency (CFE). It was found that the square infill pattern shows the maximum Fip\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathrm{F}}_{\mathrm{ip}}$$\end{document}, Fm\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathrm{F}}_{\mathrm{m}}$$\end{document}, U and SEA with values of (24.38 kN, 20.58 kN, 673.38 kJ, and 26.52) while zigzag infill pattern shows the highest CFE with a value of 0.91. The optimal infill pattern is determined using a Multi-Attribute Decision Making (MADM) method called Complex Proportional Assessment (COPRAS). The COPRAS results showed that the square infill pattern is the most effective energy absorbing structure.