### 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 language | English (US) |
---|---|

Pages (from-to) | 116-126 |

Number of pages | 11 |

Journal | Computational Materials Science |

Volume | 164 |

DOIs | |

State | Published - Jun 15 2019 |

### Fingerprint

### 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

### Cite this

*Computational Materials Science*,

*164*, 116-126. https://doi.org/10.1016/j.commatsci.2019.03.056

**Impact of solutes on the lattice parameters and elastic stiffness coefficients of hcp Fe from first-principles calculations.** / Fellinger, Michael R.; Hector, Louis G.; Trinkle, Dallas.

Research output: Contribution to journal › Article

*Computational Materials Science*, vol. 164, pp. 116-126. https://doi.org/10.1016/j.commatsci.2019.03.056

}

TY - JOUR

T1 - Impact of solutes on the lattice parameters and elastic stiffness coefficients of hcp Fe from first-principles calculations

AU - Fellinger, Michael R.

AU - Hector, Louis G.

AU - Trinkle, Dallas

PY - 2019/6/15

Y1 - 2019/6/15

N2 - 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.

AB - 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.

KW - Ab initio

KW - DFT

KW - Elastic constants

KW - Iron

KW - Lattice parameters

KW - Martensite

KW - Solutes

KW - Steel

KW - hcp

UR - http://www.scopus.com/inward/record.url?scp=85064081113&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85064081113&partnerID=8YFLogxK

U2 - 10.1016/j.commatsci.2019.03.056

DO - 10.1016/j.commatsci.2019.03.056

M3 - Article

AN - SCOPUS:85064081113

VL - 164

SP - 116

EP - 126

JO - Computational Materials Science

JF - Computational Materials Science

SN - 0927-0256

ER -