Investigation of Tensile and Impact Properties of 3D-Printed Parts with Varying Nozzle Diameters and Infill Densities

This study investigates the effects of nozzle diameter and infill density on the mechanical behavior of PLA+ parts, focusing on tensile and impact properties. I used a Bambu Lab A1 3D printer to manufacture the specimens at infill densities of 50% and 100%, with all other printing parameters fixed. The influence of nozzle diameter on structural integrity and load-bearing capacity was tested at four sizes: 0.2 mm, 0.4 mm, 0.6 mm, and 0.8 mm. The study’s results show that tensile properties and impact energy are highly correlated to both nozzle diameter and infill density. The larger the nozzle diameter, the higher the tensile stress and impact energy. Consistently enhancing the mechanical strength of a material is the increasing infill density of the polymer part. Based on the results, we can obtain some valuable insight into setting the FDM printing parameters that achieve a balance in accuracy, strength and toughness of the PLA+ parts for engineering and practical applications.