Exploring the Tribological Properties of <scp>3D</scp> Printed Polymer Composites: An Experimental Study

ABSTRACT In recent years, additive manufacturing, especially 3D printing, has been gaining more space in the production of parts and components in various industries. Among the polymer materials, polylactic acid (PLA) stands out due to its renewable sources, such as corn starch or sugar cane. This study focused on the evaluation of the coefficient of friction (CoF) and wear resistance of pins of pure PLA, pure thermoplastic polyurethane (TPU), and bronze‐filled PLA (BRO), all produced by fused deposition modeling (FDM). The pins were rubbed against a SAE 1020 steel counterpart in a pin‐on‐disc apparatus. The wear tests also included combinations of BRO/PLA and TPU/PLA (with a pattern on the surface), combined at three different percentages (25%, 50%, and 75%). Pure BRO showed the lowest wear rate ( K ≈0.9 × 10 −5 mm 3 /N m), while pure PLA exhibited the lowest CoF among the pins ( μ ≈0.24) but the highest wear ( K ≈16.7 × 10 −4 mm 3 /N m). The combination of 75% of BRO with 25% of PLA demonstrated a favorable balance between friction and wear, with a wear resistance close to BRO ( K ≈0.8 × 10 −5 mm 3 /N m) and a CoF similar to pure PLA ( μ ≈0.28). The paper extensively discusses the wear mechanisms observed on the worn surfaces, as well as the tribofilm formed on the steel disc counterpart.