Simulations and analysis of phase transformations in bcc-Fe under isothermal compression

Using EAM potential and molecular dynamics, the transition from bcc to hcp in bcc-Fe under isothermal compression along [001] orientation was simulated. The results reveal that under the stress beyond transition threshold, hcp phase begins to nucleate and then grows into flaky morphology along (011) plane of bcc phase and the system shows an over-relaxation of stress. Mean stress and hcp mass percent increase linearly with volume compression during the growth of hcp phase, and longitudinal partial stress reduces linearly with increasing of hcp phase during the whole transition process. Average potential of the atoms in hcp phase is greater than that in bcc phase.