TENSILE PROPERTIES OF LAYER-STRUCTURED HIGH-IMPACT POLYSTYRENE (HIPS) WITH VARIOUS INFILL PATTERNS FOR 3D PRINTING BY FINITE ELEMENT ANALYSIS (FEA)

Abstract

High Impact Polystyrene (HIPS), as one type of polystyrene, is water resistant and ideal for liquid handling products. In this study, the effect of infill patterns on the tensile properties of 3D printed HIPS was investigated using Finite Element Analysis (FEA). Infill pattern is the lattice mesostructured inside a 3D printed object. Seven types of infill patterns, namely honeycomb, rectilinear, line, concentric, Archimedean chords, octa gram spiral and Hilbert curve, were applied in the situational studies. A 3D model of tensile specimens following the ASTM D638 was designed on CAD software. Then, each of these infill patterns was imposed on the tensile specimen using a 3D printing slicing software which resulted in a series of G-code coordinates files. Using specially developed conversion software, layer-structured 3D models that mimic the actual 3D printed tensile specimens had been produced. Through FEA, it was found that the honeycomb infill pattern provided the highest tensile strength and strain of 3D-printed HIPS specimens. The trend in strength and strain for other infill patterns had been summarized.