Effect of infill pattern and infill density at varying part orientation on tensile properties of fused deposition modeling-printed poly-lactic acid part

Fused deposition modeling is an additive manufacturing process in which successive layers of material are deposited to create a three-dimensional object. It is the most widely used additive manufacturing process because of its ability to make specimen having difficult geometrical shape. However, building end-user functional parts using fused deposition modeling proved to be a challenging task because of a wide variety of processing parameters. In the present paper, a detailed experimental study on open source 3D printer is reported to explore the effect of various fused deposition modeling process parameters viz. part orientation, infill density and infill pattern on tensile properties and modes of failure. Poly-lactic acid filament is used to make 3D specimens. The experimental values of tensile properties are measured and critically analysed. Failure modes under various tests are studied using scanning electron microscopy. Tensile test results indicate that part orientation, infill pattern and infill density significantly affect the tensile strength. It has been observed that parts printed with flat part orientation and concentric pattern exhibit maximum tensile strength. While tensile strength has been increasing with increment in infill density. From the SEM images, it has been found that one of the major causes of failure is weak strength within and between layers for the lower value of infill density.