Introduction: With contemporary advancements in Additive Manufacturing (AM), it has become possible to obtain hull structures for spacecraft made of relatively cheap materials. The possibility of substituting super-austenitic stainless steel Avecta SMO 254 X1NiCrMoCuN20-18-7 (EN 10088) for the already used in the Starship SpaceX 304 L-Modified is focused on better thermal stability and durability in extreme conditions. The Directed Energy Deposition Arc (DED-Arc) method for AM has enabled the production of high-strength-to-weight ratios. The aim is to engage low-cost material with treatment optimization to provide greater corrosion resistance and high yield and tensile strength.

Method: For the DED-Arc, a filler wire was selected for the welding source, Fronius TPS 400i. A simulation via the RoboDK Robot Development Kit for the FANUC ARC Mate 100ID10L is provided. Additional shot pining/vibration treatment is proposed for the finished structure, which can be a substitute for the cold-worked initial metal. A comparison is made for stainless steel that has already been tested for space travel. Regimes for the manufacturing process are proposed, with representative samples of Avecta SMO 254 obtained and tested using microhardness measurements, microcracking detection, porosity measurements, interface zone assessment, and microstructural analysis.

Results: DED-Arc process applies to large-space shell manufacturing. A comparison is made with a focus on the mechanical and corrosion advantages. For Avecta SMO 254, microhardness measurements ranged from 235 to 246 HV1 and increased after treatment. The controlled parameters provided a maximum heat input of 0.7 KJ/mm, no defects, and a fine microstructure.

Conclusion: The successful use of stainless steel with AM increases the potential for multiple space missions. The advanced method shows high quality, allows cost saving,s and provides extended service life.

Funding: The author acknowledges support from project BG16RFPR002-1.014-0005.