Extrusion-based polymer 3D printing parts with isotropic strength and smooth surface finish: In-situ Thermal Radiation Assisted Fused Filament Fabrication

K. Hsu, P. Han
Arizona State University,
United States

Keywords: FDM, FFF, extrusion 3D printing, isotropic mechanical property

Summary:

In-situ Thermal Radiation (ITR) assisted extrusion-based 3D printing is a new technology capable of producing nearly isotropic mechanical properties and smooth surface finish in extrusion 3D printed polymeric parts in as-printed state. This process introduces thermal energy from focused thermal radiation into deposited polymer tracks during 3D printing, improving polymer chain diffusion and relaxation in deposited tracks and interfaces. This, in turn, increases the weld strengths of all internal interfaces in the printed part, and produces better surface finish by controlled surface reflow. This technique is shown to be capable of improving mechanical strength in print direction by a factor of 3 with less than 3 W of additional power consumption when implemented in a desktop-scale fused filament fabrication (FFF) printer. Parts fabricated using this process presents nearly isotropic mechanical strength, greater elongation before fracture, and smooth surface. In this presentation, the implementation of this technology on a FFF 3D printer and how this technology is applied to fabricate nearly isotropic part and part with smooth surface will be presented and discussed, alone with the characterizations of tensile behavior, flexural behavior, and surface morphology of fabricated parts.