Speaker
Description
The increasing demand for developing lightweight liquid hydrogen (LH₂) storage systems, particularly for aviation applications, has intensified the need for reliable multi-material structures capable of operating under cryogenic conditions. While stainless steel is commonly used for LH₂ tanks due to its excellent cryogenic performance, hybrid concepts combining stainless steel and aluminium offer significant weight reduction potential. Such concepts require robust multi-material joints capable of withstanding high thermal loading conditions while maintaining leak-tightness for LH₂ applications.
Current state-of-the-art joining technologies for aluminium–steel combinations, such as explosion welding and friction welding, can suppress the formation of brittle intermetallic Al–Fe phases due to their solid-state processing routes. However, these methods are limited in geometric flexibility, associated with high manufacturing costs, and have demonstrated limited reliability for demanding cryogenic applications.
This work investigates the potential of Wire Arc Directed Energy Deposition (WA-DED) for the fabrication of aluminium–steel transition joints for LH₂ tank systems using 316L stainless steel and ER5183 aluminium alloy. Particular attention is given to the mechanical loading of the brittle intermetallic phase at the material interface for varying joint geometries and cryogenic operating conditions. Within the LH2-LIWA-Tank project, a comprehensive finite element simulation framework was developed to analyse stress evolution during manufacturing and in-service operation. Material testing was performed over a wide temperature range to obtain temperature-dependent material data required for both welding process simulations and cryogenic service simulations. The manufacturing simulation was directly coupled to the in-service analysis by transferring residual stresses, temperature fields, and material states. Furthermore, an analytical thermo-fluidic model representing the LH₂ filling process was used to define thermal boundary conditions for the cryogenic thermo-mechanical simulations.
The numerical results were validated experimentally using a WA-DED multi-material joint manufactured at LKR Leichtmetallkompetenzzentrum Ranshofen. The combined experimental–numerical approach provides an important basis for the future development and optimization of reliable multi-material joints for cryogenic hydrogen applications.
| Speaker Country | Austria |
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| Would you like to publish your paper in the special issue of BHM "Berg- und Hüttenmännische Monatshefte" | Yes |