Influence of Thermal Cycling on Friction, Wear, and Damage Evolution of Fused Deposition Modeling of <scp>3D‐Printed</scp> Glass Fiber Reinforced Polylactic Acid Composites

ABSTRACT This research work investigated the effect of the cyclic thermo‐hygrometric aging regime between −20°C and +40°C with 0–400 cycles on the reciprocating tribological properties of fused deposition modeling (FDM) printed polylactic acid (PLA) and the same material reinforced with 10 wt.% and 15 wt.% of glass fiber GF. The samples were analyzed for wear through non‐contact laser profilometry, scanning electron microscopy, and thermal gravimetric analysis. The neat PLA showed a non‐monotonic wear profile since it was observed that the wear volume of this material increased drastically from 0.033 to 0.335 mm 3 after 200 cycles at 10 N, and finally, achieved a maximum value of 2.042 mm 3 after 400 cycles subjected to 20 N. However, the reinforcing GF changed such profile, reducing by up to 83% the wear volume. The most interesting result is that the combination of 15 wt.% of GF in a polymer subjected to 200 cycles produced a regime where the coefficient of friction (COF) was greater than unity (1.37), despite having no increase in the volumetric wear loss (Δ = 4.5%). Therefore, it is possible to conclude that there is a decoupling between the processes due to debonding of the interfaces and the third‐body wear mechanism. Factorial ANOVA ( R 2 = 99.32%) showed that Material × Cycle × Load interaction (29.39%) was the main contribution to this effect.