LUT University’s Mechanics of Materials Lab, led by Prof. Masoud Moshtaghi with strategic coordination of Gasgrid and associated with the EU-funded BalticSeaH2 initiative, aims to answer a crucial question for the clean energy transition: How do we transport hydrogen safely and reliably at scale? Our joint mechanics and material study looked beyond traditional testing to the behaviour of pipeline steels in hydrogen, where hydrogen embrittlement, the absorption of hydrogen that reduces ductility and toughness and accelerates crack initiation and growth, can compromise structural integrity and welded steel components and structures health. We generated design-relevant data, e.g. on hydrogen-based solid mechanics, manufacturing routes, pipeline steel and weld design aspects and lifetime assessment methods to qualify steels and welds for Finland’s future hydrogen backbone and its connection to the wider European network. The study shed light for hydrogen pipeline material selection by
- Identifying critical parameters for materials and mechanics of pipeline steels in hydrogen service.
- Mapping the effects of manufacturing methods and construction choices on hydrogen compatibility.
- Outlining a qualification pathway that integrates hydrogen-environment testing and hydrogen-based solid mechanics to support safe, reliable hydrogen pipeline systems in Finland, in step with European efforts and cross-border interoperability.
Why this matters?
Hydrogen will play a pivotal role in decarbonising industry, mobility, and energy systems. However, large-scale deployment depends on one non-negotiable principle: safety by design, a requirement emphasised by the Clean Hydrogen Joint Undertaking SRIA (2024) and ISO/TC 197 standards for hydrogen infrastructure. Engineering assurance must therefore be built on validated mechanics of materials, certified manufacturing routes, welding integrity, and lifetime performance under hydrogen exposure.
Finland has an ambitious, target of carbon neutrality by 2035 and is one of the Europe’s most attractive hydrogen economies due to competitive renewable electricity prices, well-functioning energy system and biogenic CO2 sources. Gasgrid is developing the national hydrogen infrastructure in Finland and advancing the cross-border hydrogen connections such as Nordic-Baltic Hydrogen Corridor, Nordic Hydrogen Route and Baltic Sea Hydrogen Collector. With industrial frontrunners and academic partners such as LUT University, Finland can provide a safety-driven, investable hydrogen ecosystem.
“Hydrogen pipelines are not a leap of faith; significant advances in steel design have been ongoing in recent years in partnership with the academic leaders. The current initiative shows that hydrogen transport safety must be designed, not assumed or oversimplified. By considering hydrogen-based solid mechanics concepts, material behaviour, manufacturing routes, and welding and operation procedures, we build reliability into Europe’s future hydrogen backbone.”
– Prof. Masoud Moshtaghi, LUT Mechanics of Materials Lab
Key messages from the study
- Hydrogen-based solid mechanics fundamentals must lead the way
Pipeline integrity for hydrogen transport should be governed by fracture-mechanics-based approaches aligned with new or evolving mechanical engineering standards such as ASME. This ensures design and assessment methods capture hydrogen-specific degradation mechanisms rather than relying on legacy assumptions. EN standards are not yet prepared compared to ASME standards.
- Test in hydrogen is essential, not just in air
Conventional testing in air does not represent hydrogen service. Qualification and documentation must include testing in hydrogen environments according to the standards, with precise traceability to:
- Pipeline steel products and their manufacturing routes.
- Construction methodology of welded tubular structures.
- Oversimplification, such as using the hardness value in air as a criterion for hydrogen pipeline design, is not effective and initiates safety risks. Reliable testing standards should be applied.
- Standardised and accurate material & mechanical testing is needed
There are scientific and practical gaps in standardised and accurate material & mechanical testing, and weld design and welding procedures for hydrogen pipelines. Parameters that are often under-reported need systematic study and transparent documentation to support safe deployment. Example of achieved results can be found here: https://doi.org/10.1016/j.matdes.2025.113950,
https://doi.org/10.1016/j.ijhydene.2023.12.068
- Hydrogen accelerates fatigue crack growth
Hydrogen exposure may lead to significant material degradation and accelerated fatigue crack growth (FCG). In our findings, up to ~100× faster crack growth in hydrogen is possible compared to methane under comparable conditions.
- This highlights the importance of hydrogen pipeline material selection. Significant advances in steel design have been ongoing in recent years in partnership with the academic leaders, and these should be clearly defined and implemented in practice.
- This means that accurate and standardised testing methods must account for hydrogen effects, and careful consideration of pipeline manufacturing routes and construction procedures is pivotal.
Safety is an engineering outcome
Like natural gas or gasoline, hydrogen is an energy carrier that demands industrial and scientific rigour. With appropriate standards, testing, and design controls for pipelines, including welds and mechanics of the pipelines, hydrogen pipelines can be engineered for robust safety and reliability.
What’s next
- Expand hydrogen-environment testing across pipeline grades, welds, and other variables.
- Close knowledge gaps in material testing in hydrogen, considering the manufacturing routes, welding procedures and lifetime assessment for hydrogen service.
- Align with emerging standards, validate through field-relevant testing and maintain a close relationship with the standard bodies and standard committees.
About the collaboration
This study was conducted by LUT University’s Mechanics of Materials Lab with strategic coordination by Gasgrid and is associated with the BalticSeaH2 project, to accelerate a safe, connected hydrogen ecosystem across the Baltic Sea region and Europe.
Connect with us: LUT Mechanics of Materials Lab led by Prof. Masoud Moshtaghi
LinkedIn: https://www.linkedin.com/company/101905605
Email: masoud.moshtaghi@lut.fi
