The Effect of Thickness, Build Orientation, and Loading Rate on the Tensile and Compressive Properties of Selective Laser Sintering Polyamide 12 Specimens

This study investigates the combined effects of build orientation, specimen thickness, and loading rate on the tensile and compressive mechanical properties of polyamide 12 parts fabricated via selective laser sintering. Unlike prior studies that examine these factors in isolation, this work systematically explores their interaction through test conditions and over 120 tensile and compression experiments. Specimens with two thicknesses (1 and 4 mm), printed in vertical and horizontal orientations, are tested at loading rates from 5 to 500 mm min −1 . Vertically printed tensile specimens exhibit brittle behavior with failure strains at a maximum of 6.5%, while edge printed exceeded 19% at a 5 mm min −1 loading rate, indicating strong anisotropy of ductility. Thinner specimens show up to 30% lower stiffness and 24% lower strength compared to thicker specimens. Increasing the loading rate enhances stiffness and tensile strength by up to 11% and 12%, respectively, but reduces ductility, especially in vertical specimens. In contrast, compressive tests reveal minimal sensitivity to build orientation, though they follow similar trends. These results offer new insights into the coupled influence of key design parameters and support the development of calibrated material models for thin‐walled, load‐bearing components in high‐precision applications.