Classical interatomic potential for quaternary Ni–Fe–Cr–Pd solid solution alloys

Research output: Contribution to journalArticle

Authors

Institutes & Expert groups

  • University of Wyoming - Mechanical Engineering
  • UFL - University of Florida

Documents & links

DOI

Abstract

In this paper, we present a new quaternary interatomic potential for the NiFeCrPd system, which is an extension on the previous NiFeCr potential. Density functional theory is used to calculate the quantities to be fitted, with particular focus on the energetics of point defects with solutes, for the potential to be used towards understanding radiation damage properties. The potential thus will enable the modeling of multi-elemental solid solution alloys consisting of up to four elements. To test the potential, we have performed atomistic kinetic Monte Carlo simulations to investigate the effect of configurational entropy on the self-diffusion coefficients. The self-diffusion coefficients are found to increase with chemical complexity, contrary to the common postulation of sluggish diffusion in high entropy alloys (HEAs). In addition, we have performed molecular dynamics simulations to elucidate the effect of Pd on vacancy diffusion and clustering in pure Ni and binary alloys. In agreement with recent irradiation experiments, our simulations show that while large vacancy clusters, such as stacking fault tetrahedra, are formed in pure Ni, Ni–Fe and Ni–Cr systems, negligible vacancy clustering is observed in Ni–Pd systems, indicating a possible effect of Pd in reducing cluster sizes.We suggest that this potential will be useful for studying the defect evolution in multi-component HEAs.

Details

Original languageEnglish
Article number065014
Pages (from-to)1-21
Number of pages21
JournalModelling and Simulation in Materials Science and Engineering
Volume26
Issue number6
DOIs
Publication statusPublished - 2 Aug 2018

Keywords

  • potential

ID: 5398890