TOOLPATH PLANNING WITH THERMAL STRESS AWARENESS FOR MATERIAL EXTRUSION ADDITIVE MANUFACTURING

Additive manufacturing has emerged as a next-generation technology for advanced fabrication. Fused Filament Fabrication (FFF) is the most widespread form of material extrusion additive manufacturing and has growing applications in large scale construction. Despite its advantages, FFF is limited by structural weaknesses introduced by cooling of the material between layers. This paper presents an approach to reduce the probability of failure for a given object under known loading conditions through improved toolpath planning which considers temperature decay. Our approach reorders the fabrication sequence to vary the time to print between layers such that the thermal stress induced in fabrication is reduced in regions most likely to fail at the expense of increasing thermally induced stress in less critical areas. In our simulation experiments, we found that our approach offers the greatest improvement when the rate of cooling is large enough for significant temperature decay to occur, but not so large that cooling occurs too quickly for the print order to have any effect. Our approach offers the potential to improve the performance of 3D printed components under known loading conditions by considering the temperature of the print in the planning of the toolpath.