High Vacuum Capable Fused Filament Fabrication 3D Printer, Part II: High-Temperature Polymers Suitable for In-Space Manufacturing

The ability to additively manufacture structures on-orbit has the potential to fundamentally alter the traditional paradigm for how large spacecraft are constructed and launched into space. The space environment presents several unique challenges for additive manufacturing, including the need to operate in a vacuum. This paper presents the design, analysis, and test results for a passively cooled fused filament fabrication (FFF) 3D printer capable of manufacturing parts out of engineering-grade thermoplastics in the vacuum of space. Four high-temperature materials were successfully printed in high vacuum, including polyetherketoneketone, carbon-nanotube–polyetherketoneketone, polyetherimide, and carbon-nanotube–polyetherimide. Over 100 test coupons were printed in a vacuum and tested to confirm the feasibility of applying the FFF process in this environment. Lessons learned were documented throughout the vacuum printing test campaigns and are discussed here. This paper is part of a two-part series. Part I presented results for using a low-temperature hotend capable of printing hobby-grade materials in high vacuum and documented initial findings and lessons learned. Part II presents the results for a high-temperature hotend capable of printing engineering-grade plastics that are suitable for on-orbit manufacturing. The combined results of the two papers in this series can be used to inform future on-orbit additive manufacturing.