Multi-layer hybrid metal structures for use in contact with hydrogen (H2MAT).

Project description

Steels (valves, etc.) in contact with H2-rich media suffer from the problem of hydrogen embrittlement, which causes them to lose mechanical properties leading, eventually, to uncontrolled breakage. The different strategies used to minimise this problem consist essentially of oversizing the components and applying surface coatings that delay the diffusion of H2 into the steel. High entropy alloys (HEA), i.e. Cantor, do not have the problem of hydrogen embrittlement that affects steels. On the contrary, they reveal slightly better mechanical properties in the presence of hydrogen, even at cryogenic temperatures.

The aim of the H2MAT R&D project is to design, manufacture and assess multilayer, high entropy alloy-interphase-steel structures as an alternative to the limitations of steel currently used in hydrogen transport applications.

The specific objectives of the project are: 

• to understand and control the physical and chemical nature of the HEA-steel interface to act as a barrier to hydrogen diffusion into steel;
• to assess the behaviour against hydrogen of non-conventional high entropy alloys, as well as their compatibility with steels;
• optimisation of the technologies proposed to produce hybrid joints with controlled interfaces, and in such a way as to minimise diffusion; and
• the technical-economic assessment of the structures obtained compared to using existing steel structures for hydrogen transport.