Effects of Infill Strategies on the Tensile Properties and Fracture Behavior of 3D‐Printed Polylactic Acid

ABSTRACT In this study, eight infill strategies with multiple infilling modes (line, grid, and honeycomb) were used in manufacturing 3D printing of a polylactic acid (PLA) by fused deposition modeling (FDM) process, and the resulting surface topographies and tensile properties were reported. The results showed that the grid/line/grid and honeycomb/line/ honeycomb samples with sandwich structures had the best tensile fracture resistance, which depended directly on the degree of quality of the interlayer. Based on the analysis of the scanning electron microscopy (SEM) of the fracture surface, the improving tensile properties of 3D samples in sandwich structures with line in core were attributed to effective raster, layer bonding, and fewer voids. The finite element (FE) simulation was performed on 3D‐printed parts to predict von Mises stress and tensile strength, which made it possible to reduce the design time to improve the tensile behavior of 3D‐printed structures.