Modified embedded atom method potential for Fe-Al intermetallics mechanical strength: A comparative analysis of atomistic simulations

Muhammad Zeeshan Khalid,Jesper Friis,Per Harald Ninive,Knut Marthinsen,Inga Gudem Ringdalen,Are Strandlie

doi:10.1016/j.physb.2021.413157

Abstract

The structural and mechanical properties of Fe-Al compounds (FeAl, Fe2Al, Fe3Al, FeAl2, FeAl3, Fe2Al5) have been studied using modified embedded atom method (MEAM) potentials. The equilibrium lattice constants, formation enthalpies, and elastic properties have been investigated and compared with other studies. The calculated lattice constants show good agreement with the embedded atom method (EAM) and density functional theory (DFT) calculations and with experiments. All Fe-Al compounds are mechanically stable according to the elastic constants restrictions. The calculated bulk modulus of the compounds does not show a linear relation with Fe concentration, which is most probably caused by the mechanical anisotropy of Fe-Al compounds. However, comparison of the Fe-Al mechanical properties of MEAM, DFT and EAM-based approaches and experiments show non-consistent differences, which reflects uncertainties with several of these methods, due to assumptions and simplifications imposed during calculations. In general, DFT calculations are closer to experimental observations than semi-empirical potentials. Comprehensive comparisons are made based on theoretical and experimental methodologies.

Highlights

Fe-Al compounds have been gaining a lot of attention due to their increased industrial interest owing to the light-weight, corrosion resistance and high-temperature resistance behavior [1,2,3]
We have investigated the structural and mechanical properties of Fe-Al compounds (FeAl, Fe2Al, Fe3Al, FeAl3, Fe2Al5) analyzed by semi-empirical interatomic potentials, i.e. the modified embedded atom method (MEAM) method [9,13]
Molecular dynamic (MD) simulations offer an opportunity of studying larger systems

Summary

Introduction

Fe-Al compounds have been gaining a lot of attention due to their increased industrial interest owing to the light-weight, corrosion resistance and high-temperature resistance behavior [1,2,3]. FeAl compounds including Fe3Al, FeAl, Fe2Al5, FeAl2 and FeAl3 have been the main focus of research in many different industrial areas, for example, hightemperature structural materials, composite materials, protective coatings for materials and functional materials. Many researchers have performed atomistic simulations to predict the mechanical strength of Fe-Al compounds [6,7,8,9,10]. Zhang et al [6] studied the structural and mechanical properties of these compounds by EAM simulations. Liu et al [10] studied the mechanical and electronic properties of Fe-Al compounds by an ab-initio method. Liu et al [11] studied the FeAl compound and calculated the elastic properties from first-principles calculations. Niu et al [12]

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Discussion

Conclusion