CHALLENGES

Hydrogen, the energy carrier of the future, has characteristics that make working with it extremely complex: (i) it is the lightest chemical element in existence, (ii) it is easy to associate with other elements by changing their properties, and (iii) it has a low volumetric energy density.

These particular characteristics mean that the treatment of hydrogen presents many challenges. Among them, there are two that H2MAT+ wants to address: embrittlement and efficient storage.

Embrittlement

For a metallic structure to suffer a hydrogen embrittlement fracture, the first challenge considered, three elementary conditions must be present at the same time:

That the material is susceptible, i.e. that it meets certain microscopic characteristics related to its mechanical properties.
That there is a high tensile stress and/or cyclic loading sufficient to cause cracks.
A hydrogen source is or has been in contact with the material.

Of the three previous conditions, work will be carried out on the first one, defining new metallic structures that can work in contact with hydrogen with lower susceptibility than the current ones. This activity will be based on a prior evaluation and assessment of these materials that currently work in environments with a high hydrogen content.

Storage complexity

Achieving materials and combinations of materials that can work in hydrogen-rich environments will be the first major challenge of this project, but given the synergies associated with understanding how materials share in these environments, there will also be a secondary objective of characterising materials that could allow hydrogen to be stored efficiently in the solid state.

Another challenge of the project is the establishment and development of sufficient knowledge and experimental capabilities to investigate applications subject to hydrogen-assisted corrosion, embrittlement and fatigue. These capabilities will enable an understanding of the effect of hydrogen on both existing metallic materials and those to be developed in the project. In particular, it will have the ability to measure and evaluate how hydrogen is absorbed, adsorbed and desorbed by the material and how these interactions affect its properties, both during and after contact with a hydrogen source.