ABSTRACT This research work explores the effects of printing parameters, namely infill percentage (40%, 60%, 80%), layer height (0.3, 0.35, 0.4 mm), and print speed (40, 50, 60 mm/s) on the microhardness, tensile, and ratcheting fatigue behavior of the 3D printed composites. Microhardness values showed an increment of 2%–3%, depicting a direct relationship with infill percentage. Layer height and print speed were inversely related as the values showed a decrement of 5%–7%. Increasing infill percentage and layer height showed improvements in tensile properties, while an increase in print speed showed a decline of 6%–8% in strength. There was an inverse trend between infill percentage and ratcheting fatigue life, showing a decline in fatigue life by 11%–13%, whereas layer height had a positive increment of 13% in the fatigue life. Moderate print speed revealed higher strain accumulation, indicating nonlinear interdependencies. The effects of these parametric interactions on the mechanical properties were also discussed using analysis of variance (ANOVA) approach. Fractography analysis revealed the existence of striations‐like features and quasi‐brittle failure mechanisms, characterized by delamination and fiber pullouts. The nature of ratcheting fatigue behavior of this material is not yet well documented in the existing literature, hence the authors attempted to understand how asymmetric loading affects their fatigue life.
Nayak et al. (Sun,) studied this question.