Markus Brotsack, IMPACT INNOVATIONS GMBH
Reeti Singh, IMPACT INNOVATIONS GMBH
Ján KONDÁS, Impact Innovations GmbH
Markus Brotsack, International Sales, IMPACT INNOVATIONS GMBH
Space propulsion applications require lightweight materials that can withstand high stresses at elevated temperatures. Niobium has a very low density compared to other refractory metals but high strength, i.e. a high strength-to-weight ratio. The material also shows high thermal conductivity and a low ductile-to-brittle transition temperature. This low transition temperature is advantageous for space applications because it shows excellent resistance to high-frequency vibrations at cryogenic temperatures. Furthermore, C-103, a niobium, hafnium, and titanium alloys used for space propulsion applications, have a high melting point at around 2.350°C and show strong stability at elevated temperatures, too.
Currently, many investigations around C-103 material for in-space propulsion systems for satellites are happening in the space industry. Right now, one way to manufacture in-space propulsion nozzles is to machine them out of bulk material. This is on the one hand side a huge waste of material, i.e. not very sustainable. On the other hand side this adds a hug amount of costs, because C-103 material is a high price material. Machining in-space propulsion nozzles out of bulk material also takes a long time, i.e. adds significant costs to the final part. Additionally, C-103 is not easy to weld, which means it is not easy to use this material in laser based powder bed fusion systems for example. Therefore, Cold Spary technology can be an economic alternative manufacturing method for C-103 propulsion nozzles.
This work shows the feasibility of Cold Spray Additive Manufacturing (CSAM) technology to produce a C-103 test part as a first step for future nozzle designs for different space applications. It is essential for the application to have as thin walls as possible to get down the take-off weight of the satellites. A tube of around 135 mm in length and 2 mm in wall thickness has been manufactured using CSAM. The manufacturing process will be presented in detail, in pictures and videos.
It has been proven that C-103 can be sprayed with high deposition efficiency using cold spray technology. Deposition efficiency of around 92% with a 4 kg/h deposition rate was observed. Both properties make cold spray cost-effective for manufacturing in-space propulsion nozzles with C-103 niobium alloy. Furthermore, microstructural and mechanical properties of cold-sprayed C-103 have also been investigated.