Understanding High-Temperature Oxidation of Nickel- and Iron-Based Alloys in Hydrogen-Rich Environments for Energy Applications

ongoing

The project aims to comprehensively study the high-temperature oxidation behaviour of NiCr and FeCr alloys with alloying additions of e.g., Ti, Mn and Si in the wet/hydrogen-containing atmospheres with emphasis on the growth mechanisms and failure of surface Cr-oxide scales. While these materials have been well-studied in oxygen and air, their performance in the atmospheres than can be encountered in hydrogen power plants and fuel cells, remains unexplored. This research is therefore relevant to the ongoing transition towards hydrogen as a sustainable energy source. Understanding how Ni- and Fe-based materials behave in such conditions is essential for developing more efficient and durable components for power generation. The project will utilize a combination of thermodynamic modeling (ThermoCalc, FactSage) and advanced experimental techniques, including e.g., oxidation testing, Scanning Electron Microscopy, X-Ray Diffraction and TEM/APT (Transmission Electron Microscopy/Atom Probe Tomography). The use of correlative TEM/APT will enable the study of grain boundary diffusion and selective oxidation, providing insights into fast diffusion pathways and oxidation mechanism at the atomic level. Oxygen isotopes will also be used as tracers to allow for quantitative analysis of the elemental distribution providing unique insights into the oxidation mechanisms, crucial for correlating microstructural features with oxidation kinetics and identifying the role of minor elements in material degradation processes. The research will be conducted in an iterative approach, refining theoretical models based on experimental findings to optimize alloy compositions for high-temperature, hydrogen-rich environments. This comprehensive approach will not only advance the fundamental understanding of oxidation processes but also contribute to the development of materials for hydrogen applications, supporting the EU’s green energy transition and reducing CO2 emissions.