Enhancing mechanical properties of FDM 3D-printed parts with ultrafast laser postprocessing

This study investigates the use of ultrafast lasers for postprocessing fused deposition modeling 3D-printed parts, focusing on improving surface roughness and analyzing its corresponding effects on tensile strength and fatigue life. We explore the adoption of high repetition rate ultrafast laser light and raster scanning techniques to address the limitations associated with as-deposited surface roughness in 3D-printed objects. By employing a design of experiment framework using Taguchi's orthogonal arrays, we analyze the effects of various laser parameters on the surface finish and mechanical integrity of printed polylactic acid parts. Our study indicates significant enhancements: a 90% reduction in surface roughness, a 20% increase in ultimate tensile strength, and a 165% increase in high-cycle fatigue life, showcasing the considerable benefits of ultrafast laser processing. We demonstrate that low-thermal-impact surface processing can substantially elevate the quality and durability of 3D-printed materials. The analysis points to the importance of controlling certain factors during the laser postprocessing phase, as they impact surface conditions and broader material properties. This work positions ultrafast laser processing as a viable technique to bridge the gap between additive manufacturing and traditional fabrication methods, particularly in the context of improving the surface quality and structural performance of 3D-printed thermoplastics. The outcomes could significantly benefit industries where additive manufacturing is prevalent by expanding the practical applications of 3D-printed components.