Modelling Internal Oxidation in Ferritic Stainless Steels
Description of the oxidation behavior of alloys at high temperatures requires apart from testing and post-exposure analysis also predictive models that capture the interaction between thermodynamic and kinetic processes of the respective reactions.
Our work involves developing a modelling framework to simulate processes occurring within oxidizing samples. The framework combines thermodynamic calculations, performed using Thermo-Calc software to describe phase formation and transformation, with kinetic modelling of the diffusion processes. This combination enables a consistent description of materials oxidation behavior over time.
By linking thermodynamics with diffusion kinetics, the model successfully predicted internal oxidation of Cr in Fe-Cr alloys, an effect commonly observed in alloys with low Cr-content or upon Cr depletion. The model correctly predicts elemental profiles, formation of complex oxide phases and, as shown in the figure, the oxidation depth of internal oxidation. The simulations provide information on alloy microstructural changes that are difficult to determine experimentally and help interpretation of laboratory results.
Potentially the approach can support the design of alloys with improved oxidation resistance. Predicting material oxidation behavior may help streamline alloy development, lower experimental costs, and contribute to a better understanding of high-temperature oxidation mechanisms.
Dr.-Ing. Dmitry Naumenko
Group leader “High Temperature Corrosion and Corrosion Protection” (IMD-1)
- Institute of Energy Materials and Devices (IMD)
- Structure and Function of Materials (IMD-1)
Room 4c