Atomistic simulations of pressure-induced phase transformation in iron-based alloys

• Applicant: Professorin Dr. Nina Merkert
• Subject Area: Computer-Aided Design of Materials and Simulation of Materials Behaviour from Atomic to Microscopic Scale ; Theoretical Condensed Matter Physics
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560322345

Materials under high-pressure conditions change their microstructure, the electrostatic interactions, and the chemical bonding. In particular, the high-pressure phase of iron has been studied extensively because it is ubiquitous in multiple areas from geophysics to engineering. It is well known that iron shows a pressure induced phase transformation from the body-centered cubic to the hexagonal close-packed phase at around 13 GPa. However, the role of interstitial and alloying elements in the pressure-induced transformation process as well as the influence of magnetism on the interplay between plasticity and phase transition is still unclear. In particular, the role of hydrogen on the transformation is open, although the transformation in hydrogen-loaded samples is supposed to be accompanied by drastic changes of the unit cell volume. A goal of this project is therefore to study the effects of the interstitial elements hydrogen and carbon in iron by molecular dynamics simulations to explain important morphological changes such as hydrogen embrittlement. Furthermore, we will analyze the magnetic structure during pressure-induced transformation in Fe using magnetic potentials and spin-lattice dynamics allowing deformation and transformation properties to be described on the basis of the magnetic structure.

• DFG Programme: Research Grants