Impact of solutes on the lattice parameters and elastic stiffness coefficients of hcp Fe from first-principles calculations

Michael R. Fellinger, Louis G. Hector, Dallas R. Trinkle

Research output: Contribution to journalArticle

Abstract

The hexagonal close-packed (hcp) ε-martensite phase in steels nucleates from the γ-austenite parent phase and can undergo further transformation to the α -martensite phase or exist as a metastable phase depending on temperature, mechanical loading, and alloy chemistry. The solute-dependent lattice parameters and elastic stiffness coefficients C ij of hcp Fe influence the mechanical properties of steels containing the ε-martensite phase, as well as the martensitic transformations between the phases. We use density functional theory to calculate the lattice parameters and C ij of single-crystal hcp Fe as functions of solute concentration in the dilute limit for the substitutional solutes Al, B, Cu, Mn, and Si, and the octahedral interstitial solutes C and N. Our computationally efficient methodology separates the solute dependence of the C ij into lattice strain and chemical bonding contributions. The computed data can be used to estimate the effect of solutes on polycrystalline elastic moduli and the strain energy associated with martensitic transformations. The data can also serve as inputs to microstructure-based models of multiphase steels containing the ε-martensite phase.

Original languageEnglish (US)
Pages (from-to)116-126
Number of pages11
JournalComputational Materials Science
Volume164
DOIs
StatePublished - Jun 15 2019

Keywords

  • Ab initio
  • DFT
  • Elastic constants
  • Iron
  • Lattice parameters
  • Martensite
  • Solutes
  • Steel
  • hcp

ASJC Scopus subject areas

  • Computer Science(all)
  • Chemistry(all)
  • Materials Science(all)
  • Mechanics of Materials
  • Physics and Astronomy(all)
  • Computational Mathematics

Fingerprint Dive into the research topics of 'Impact of solutes on the lattice parameters and elastic stiffness coefficients of hcp Fe from first-principles calculations'. Together they form a unique fingerprint.

  • Cite this