By Muhammad OsamaReviewed by Lexie CornerApr 17 2025A recent article in Advanced Engineering Materials explores the development of aluminum-scandium (Al-Sc) alloys tailored for hydrogen storage valve applications. The study responds to growing demand for lightweight, high-strength, and corrosion-resistant materials that can endure the high pressures associated with hydrogen storage, particularly in the transport sector.
Image Credit: Jantov/Shutterstock.com
Advances in Lightweight Materials Technology
Aluminum alloys continue to attract interest in transport and energy applications due to their strength-to-weight ratio, corrosion resistance, and weldability.
Incorporating small amounts of scandium, typically between 0.05 and 0.5 weight percent, improves these alloys through grain refinement, enhanced grain boundary stability, and precipitation hardening via the formation of Al3Sc particles during heat treatment. These microstructural changes contribute to increased mechanical strength and thermal stability.
The widespread adoption of Al-Sc alloys has been limited in part by the high cost and limited availability of scandium. However, advances in extraction technology and the discovery of new sources have improved the material’s accessibility, making it more viable for industrial use.
Alloy Development and Processing Approach
This study evaluated multiple aluminum alloy series (3xxx, 5xxx, 6xxx, and 7xxx) with different scandium and zirconium (Zr) additions to identify compositions suitable for hydrogen storage valves. The objective was to improve mechanical performance—specifically hardness and tensile strength—through targeted alloy design and processing.
The analysis included both commercial and experimental alloys. These included 5083 with 0.2 wt% scandium, selected for its corrosion resistance and weldability, and AlSi16Mg1Sc0.4, a hypereutectic composition developed for additive manufacturing. The alloys were processed using casting, extrusion, forging, and laser powder bed fusion. Heat treatment parameters, including temperature and aging duration, were varied to optimize mechanical properties.
Testing methods included Vickers and Brinell hardness measurements and tensile testing. Prototype hydrogen storage valves were also fabricated to assess the mechanical suitability of selected alloy compositions under application-relevant conditions.
Effects of Scandium and Zirconium Alloying
The results showed that adding 0.2 wt% scandium to alloy 5083 significantly improved its hardness and tensile strength, making it suitable for hydrogen valve applications.
The optimal processing route included extrusion at 450 °C, followed by water quenching and aging at 260 °C for 24 hours. Under these conditions, the alloy achieved a tensile strength of 345 MPa and a yield strength of 218 MPa. Notably, omitting solution heat treatment prior to extrusion further contributed to mechanical performance gains.
The combined addition of scandium and zirconium enhanced the thermal stability of Al3Sc dispersoids, improving high-temperature performance. Among the tested compositions, the 5083 + 0.2 wt% Sc alloy exhibited the best overall mechanical properties.
The 3003 alloy showed a maximum hardness increase of 49.6 %, while 5083 showed an increase of 34 %. In contrast, the 6xxx and 7xxx series alloys displayed smaller improvements, likely due to the limited hardening effect of scandium under standard heat treatment conditions.
The study also addressed the cost of using scandium. Although scandium remains expensive (currently priced above $2,000 per kilogram), recent advances in extraction methods and access to new raw material sources may reduce costs over time and improve feasibility for broader industrial use.
In addition to conventional processing, the research highlighted the applicability of Al-Sc alloys in additive manufacturing. The hypereutectic alloy AlSi16Mg1Sc0.4 achieved a hardness of up to 105 HV and showed good processability using laser powder bed fusion. The ability to tailor microstructures through AM was identified as a key benefit, enabling the fabrication of complex components optimized for hydrogen-related applications.
Applications in Hydrogen Storage and Related Systems
This research highlights the potential of Al-Sc alloys for use in hydrogen energy systems, particularly in storage valves subjected to high internal pressures. As hydrogen continues to be adopted as a clean fuel, there is a growing need for materials that combine low density with high mechanical strength. Al-Sc alloys meet these criteria and are well-suited for components such as hydrogen storage tanks in transportation applications.
Their mechanical performance, corrosion resistance, and weldability make them a feasible alternative to heavier metals like steel. The weight reduction associated with aluminum-based components can contribute to improved fuel efficiency and lower greenhouse gas emissions.
Additionally, these alloys are compatible with additive manufacturing processes, which enables the production of geometrically complex components with optimized properties. The materials also show good resistance to hydrogen embrittlement and offer the durability needed for long-term use in hydrogen storage environments.
Conclusion and Future Work
The research demonstrates that aluminum-scandium alloys, particularly 5083 with 0.2% scandium, offer a viable solution for hydrogen storage valve applications. Optimized heat treatment and processing methods further enhance their mechanical properties. The study also confirms the potential of these alloys in additive manufacturing, especially where microstructure tailoring is critical.
Future work should include detailed microstructural characterization, long-term corrosion testing in hydrogen environments, and studies on hydrogen embrittlement behavior. Continued development of scandium sourcing and processing technologies will also enable broader adoption of these alloys in hydrogen storage systems and other energy-related applications.
Download your PDF copy now!
Journal Reference
García-Moreno, F., et al. Development of Aluminum Scandium Alloys for Hydrogen Storage Valves. Advanced Engineering Materials, 2500330 (2025). DOI: 10.1002/adem.202500330, https://advanced.onlinelibrary.wiley.com/doi/10.1002/adem.202500330?af=R
Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.