Hydrogen gas plays a key role in the European energy transition strategy. Solar power, wind power, biomass or hydropower are renewable resources, which already contribute to the sustainable supply of electric energy. However, temporal fluctuations of renewable resources, lack of long-term storage capacities and the lack of transport and distribution grids complicate exploiting the full potential of renewable resources in Europe. Therefore, the power-to-gas (PtG) concept is currently being implemented and tested in European regions with high potential in solar and wind power but low demand for electric energy. The basic idea is storing electric energy that is generated from renewable resources chemically as gaseous hydrogen, instead of disconnecting solar farms and wind plants from the electric grid.

When transmitting and storing compressed hydrogen gas, safety is most important. Leakage of hydrogen gas through cracks may cause high danger for life, as the risk of explosions increases. Hydrogen embrittlement (HE) can lead to such cracks. Therefore, appropriate safety factors must be considered in designing pipes, valves and storage tanks. The safety factors mainly depend on the HE resistivity of the chosen materials.

This work presents a comprehensive material screening of high-strength austenitic steels. For this purpose, the hollow sample technique was developed and applied at room temperature and with an internal pressure of 200 bar. Eight stainless steels with ultimate tensile strengths between 700 and 1200 MPa were selected and tested with a strain rate of 5 10^-6 s^-1. The materials were classified according to their remaining ductility (HE%) in hydrogen atmosphere in three groups, i.e. resistant (HE%>75%), medium (25%<HE%<75%) and susceptible (HE%<25%). In addition, a database was established with more than 200 measurements from literature.

It is shown that the hydrogen resistivity of high-strength austenitic steels mainly depends on the nickel and chromium content. While nickel increases the austenite stability, chromium can have a decreasing effect. Based on this classification, a HE map was established, in which an area of H₂ readiness was identified. A comparison with the material recommendations given by TÜV Süd revealed good agreement between the new established hydrogen embrittlement map and field experiences.