CarboEDiffSim: Simulation of Carbon electro diffusion in Iron with phase change
Axes: Simulation & Modeling, Materials & Structure Design
Leaders: Takashi TOKUMASU (IFS, TU) & Patrice CHANTRENNE (MATEIS, INSA-Lyon)
Participants: M. NAKAUCHI, N. UENE, K. ISHIKAWA, K. NAKAJIMA
Carbon based iron alloys (steels) are widely used for various applications. New treatments are under development to increase the variety of properties. Among them, electromigration allows increasing C diffusion in the direction of the electric field. This might be used to get non-isotropic microstructures and mechanical properties or to decrease the duration of the thermal treatment.
The description of the physical phenomena leading to the drift velocity of C in Fe under the influence of an electric field has been proposed by Nernst Einstein. However, this has been done only for single phase systems. In this project, C concentration profile and temperature level induce a phase change and the use of the drift velocity predicted by the Nernst Einstein Theory to predict the phase change front propagation is not relevant.
This project is organized on three stages:
- simulation of C electrodiffusion at the atomic scale, first in single phase system to correlate the simulation results to the classical results
- simulation of the solid phase change in Iron due to C diffusion
- simulation of the solid phase change in Iron due to C electrodiffusion.
The two latter stages require a preliminary accurate study of the interatomic potential using ab initio calculations in order ensure that phase change might be simulated using MD.