14 February, 2025
The "Finishing Technologies for Additively Manufactured Complex Parts" (FITFAME) project is part of the General Support Technology Programme (GSTP), sponsored by ESA (European Space Agency).
The Programme focuses on leading-edge technologies that are not yet space-ready and develops them for future missions. These missions aim to help us discover the Universe, understand our environment, improve navigation, educate, and save lives.
It brought together BMT Aerospace, SABCA, CRM Group, APworks, and Chimiderouil to tackle the rough surfaces often found on 3D-printed metallic parts.
Additive Manufacturing (AM), or 3D printing, is amazing for creating complex shapes and reducing material waste. However, the parts often come out with rough surfaces that need extra finishing to meet aerospace standards. The FITFAME project aimed to improve these finishing technologies, making AM parts more suitable for high-performance use.
The main goal was to advance finishing technologies from lab-tested solutions (Technology Readiness Level 4) to prototypes used in real-world conditions (Technology Readiness Level 5 – 6). They reviewed existing surface technologies, selected specific case studies, developed and tested complete AM processes, and benchmarked results against conventional methods.
The project successfully improved the handling of complex 3D-printed parts using advanced techniques like Laser Powder Bed Fusion (LPBF) with Scalmalloy and Electron Beam Melting (EBM) with Ti6Al4V. These advancements pave the way for better performance and efficiency in aerospace applications.
Two specific use cases were selected:
This component was redesigned using LPBF technology to improve hydraulic performance while reducing weight by up to 10%. Various finishing techniques were tested including abrasive flow machining; chemical polishing; electrochemical polishing; DLyte™, Coolpulse™, MMP technology™ processing. The testing campaign showed significant improvements in hydraulic performance compared to machined counterparts.
The second use case focuses on a reusable launcher's steering fin actuator gearbox. The FITFAME project aimed to produce the output ring gear through additive manufacturing, achieving a significant weight reduction compared to conventionally machined equivalents.
Titanium was selected for its excellent weight reduction potential. However, it presents challenges due to lower stiffness and typically poor tribological performance. To address these issues, a tailored geometrical redesign—achievable only through additive manufacturing—was implemented to compensate for the material's shortcomings.
The manufacturing sequence began with producing a near-net shape blank using Electron Beam Additive Manufacturing (EBAM). Only the interfaces and gear teeth were machined, utilizing state-of-the-art skiving processes. Various surface finishing techniques such as corundum blasting, chemical polishing, stream finishing, and high-energy polishing were employed to enhance the quality of remaining surfaces. Through trials on coupons and full-size parts, valuable data was gathered regarding these processes' capabilities.
Finally, a case hardening heat treatment was applied before subjecting the components to mechanical strength performance testing. Despite titanium's inherent limitations for gear applications, satisfactory mechanical performance was achieved thanks to meticulous design and an end-to-end developed manufacturing process.y
The benefits realized from finished complex AM components include:
Next steps involve completing flight qualification campaigns for the AM-based hydraulic manifold. This is in preparation for engineering modifications within Ariane's thrust vector actuation system. Additionally, integrating REACH-compliance requirements throughout the involved processes is also a priority.
The FITFAME project has made great progress in improving additive manufacturing (3D printing) for creating complex parts. It tackled the problem of rough surfaces on these parts, making them smoother and cleaner. This improvement helps the aerospace industry adopt 3D printing more widely, leading to better performance and efficiency. For the ring gear use-case, the next step has to address improved heat treatment distortion control along with dynamic and functional performance testing.
The advancements from this project pave the way for future innovations in aerospace technology.
