Solubility of carbon close to defects in bcc iron I
The aim of the present project is to investigate the solubility and segregation behaviour of carbon in the strain field of defects in bcc Fe, such as grain boundaries and dislocations. In order to be able to apply large scale molecular dynamics (MD) methods, we currently evaluate the transferability of different empirical potentials.
As one test case the carbon solubility in bcc Fe as a function of the lattice strain is studied by ab-initio calculations based on density-functional theory (DFT) and by different embedded-atom method (EAM) potentials as well as by the modified embedded-atom method (MEAM) and the results are compared. The EAM potential types differ by their parametrization, construction and fitting, whereas the MEAM differs from the EAM potentials by its formalism including angular dependent bonding.