Compressive Strength of 3D Fabricated Parts: Experimental and Numerical Studies

Abstract

Additively manufactured (AM) parts have mechanical properties that differ from the ones of the traditionally manufactured parts. The difference in the mechanical properties is due to the AM’s specific working manner of adding the material in layers. By consulting the available literature on this matter, it is concluded that most of the research papers are concerning the tensile strength of the parts leaving only a small number of papers dealing with the compressive strength of the parts. The aim of the paper is to make contribution in this particular research area. As an AM process we are using the fused filament fabrication (FFF) process and polylactic acid (PLA) material. The study also explores the influence of the infill pattern on the compressive stress of the parts. Samples are designed and tested according to the ISO 604 standard. Three samples size 25x25x25 mm were tested on SHIMADZU AG-X 250 kN for the experimental study and in LS-Dyna and HypeMesh for the numerical study. Results showed correlation between the results in the experimental and numerical study. Lowest values for the compressive strength were achieved by the concentric infill samples. This is one addition in the studies correlating the process parameters to the mechanical properties. These types of studies are valuable input in the design process and material selection process for a particular application.