Dislocation Properties and Peierls Stress of BCC Iron Based on Generalized-Stacking-Fault Energy Surface by Using First Principles Calculations

Abstract

  We calculate the generalized-stacking-fault (GSF) energy surface of BCC iron by using first principles density functional theory (DFT). We employ the semidiscrete variational Peierls-Nabarro (SVPN) model to investigate the edge dislocation properties of BCC iron. The dislocation core width and Peierls stress are estimated as 0.20 nm and 80 MPa, respectively. We also estimate the GSF energy surface and dislocation properties using two different embedded atom method (EAM) potentials and compare with the DFT results.