First principles study on electronic structure and corrosion resistance of Fe-N-Cr

The electronic structure and corrosion mechanism of Fe-N-Cr based on density functional theory by using the first principles was studied. The crystal cell structures of Fe, Cr, Fe-N and Fe-N-Cr were built and the electronic structure parameters, such as the energy, charge density, band structure, density of states and the local density of states were calculated, and then the corrosion resistant mechanism of high nitrogen stainless steels was analyzed. The results showed that there was an obvious charge transfer between Fe and N after solid solution, forming the ionic bonds between Fe and N. The energy band of Fe was wider than Fe-N and Fe-N-Cr, which indicated that the atomic orbital extension of Fe was stronger. Bonding peak height of Fe, Fe-N, Fe-N-Cr successively increased, the number of bonding electrons increased, and Fe-N-Cr had the most stable structure with best corrosion resistance property.