Fraunhofer-Gesellschaft
The ASPIRER project develops and validates an additive Aerospike engine manufactured in INCONEL 718.In collaboration with the Institute of Aerospace Engineering at TU Dresden, the project demonstrates how additive manufacturing enables the realization of complex, actively cooled Aerospike rocket engines, a concept that has remained largely experimental for over 60 years.Funded by the European Space Agency (ESA), ASPIRER addresses one of the key challenges in modern propulsion: improving efficiency under varying atmospheric pressures.
Why an Additive Aerospike Engine?
Compared to conventional bell nozzles, the Aerospike concept offers:
- Altitude-adaptive thrust optimization
- Potential fuel savings up to 30%
- Improved theoretical propulsion efficiency
- Enhanced performance for reusable launch systems
The major historical limitation:The spike operates in the hot gas stream and requires efficient cooling to prevent melting.Additive manufacturing with integrated near-surface cooling channels now makes this feasible.
Manufacturing Chain
The additive Aerospike engine is produced using:
- Laser Powder Bed Fusion (LPBF)
- Heat treatment
- Precision machining of functional surfaces
- Thermal coating of the spike
- Welding of shroud and spike
The complete process chain was validated regarding:
- Mechanical properties
- Manufacturability
- Process stability
- Destructive and non-destructive testing
Publications:
https://doi.org/10.2351/7.0001121
https://doi.org/10.1007/s12567-022-00476-7#
https://doi.org/10.13009/EUCASS2025-552
Links:
https://www.iws.fraunhofer.de/de/technologiefelder/additive-fertigung-und-oberflaechentechnik/pulverbettverfahren-und-drucken/aspirer.html
Contact:
M.Sc. Samira Gruber
Fraunhofer Institute for Material and Beam Technology IWS
Winterbergstr. 28
01277 Dresden
samira.gruber@iws.fraunhofer.de
Phone +49 351 83391-3515