Failure analysis of 3D-printed PLA components: Impact of manufacturing defects and thermal ageing

• Overview of the process parameters in FDM technique. • Design and fabrication of intact and defected 3D-printed parts. • Accelerated thermal ageing on intact and defected components. • Fracture studies of polymeric additively manufactured structural components. • Influence of raster orientation and thermal ageing on the failure behavior of parts. The significant increase in applications of additive manufacturing has led to various investigations in this field. Three-dimensional (3D)-printed parts might be subjected to different environmental conditions during their service life. Therefore, a profound knowledge on this subject can significantly help to increase structural performance of these parts. In the present study, effects of accelerated thermal ageing on the mechanical behavior of 3D-printed parts has been investigated. To this aim, a natural environment has been simulated and the related effects are investigated by means of accelerated thermal ageing with temperature in the range of −5 °C to 35 °C. Moreover, the current study describes influence of manufacturing defect on the fracture behavior of 3D-printed components. Since defects and anomalies might be occurred during 3D printing process, fabricated parts can show different mechanical behaviors. In the present investigation, intact and defected test coupons with different raster orientations were printed and examined. In detail, polylactic acid material was used in fabrication of the specimens based on the fused deposition modeling process. These groups of specimens were also aged and subjected to tensile load. The documented results indicate effects of thermal ageing on the structural integrity of intact and defected specimens. The outcome of this study can be utilized for future design and next computational modeling of 3D-printed polymer parts.