The impact of environmental degradation on the fatigue life of fused filament fabricated polylactide

Purpose Understanding the effects of environmental aging is crucial for the implementation of additively manufactured components in diverse applications, including biomedical devices and structural systems. This study aims to investigate the impact of hydrolytic degradation on the fatigue life of fused filament fabricated polylactide. Design/methodology/approach An experimental framework combining fatigue testing and differential scanning calorimetry (DSC) was used to explore the relationship between hydrolytic degradation, crystallinity evolution and fatigue life. PLA specimens produced with two raster orientations (+45°/−45° and 0°/90°) was environmentally aged in phosphate-buffered saline at 37°C for durations of four (W4) and 12 (W12) weeks. Findings The results of this study show correlation between the degree of hydrolytic degradation and reduced fatigue life, accompanied by changes in material crystallinity. The findings of this paper underscore the role of environmental exposure in determining the long-term mechanical integrity of biodegradable fused filament fabricated components. Originality/value This study offers a comprehensive assessment of how controlled environmental aging affects the fatigue behaviour of PLA specimens with varying raster patterns. This study’s unique contribution lies in linking crystallinity alterations because of hydrolytic degradation with fatigue life, providing valuable insights for the design of biodegradable structures.