Publication detail

Strength and Brittleness of Interfaces in Fe-Al Superalloy Nanocomposites under Multiaxial Loading: An ab initio and Atomistic Study

ŠESTÁK, P. FRIÁK, M. HOLEC, D. VŠIANSKÁ, M. ŠOB, M.

Original Title

Strength and Brittleness of Interfaces in Fe-Al Superalloy Nanocomposites under Multiaxial Loading: An ab initio and Atomistic Study

Type

journal article in Web of Science

Language

English

Original Abstract

We present an ab initio and atomistic study of the stress-strain response and elastic stability of the ordered Fe3Al compound with the D03 structure and a disordered Fe-Al solid solution with 18.75 at.% Al as well as of a nanocomposite consisting of an equal molar amount of both phases under uniaxial loading along the [001] direction. The tensile tests were performed under complex conditions including the effect of the lateral stress on the tensile strength and temperature effect. By comparing the behavior of individual phases with that of the nanocomposite we find that the disordered Fe-Al phase represents the weakest point of the studied nanocomposite in terms of tensile loading. The cleavage plane of the whole nanocomposite is identical to that identified when loading is applied solely to the disordered Fe-Al phase. It also turns out that the mechanical stability is strongly affected by softening of elastic constants C′ and/or C66 and by corresponding elastic instabilities. Interestingly, we found that uniaxial straining of the ordered Fe3Al with the D03 structure leads almost to hydrostatic loading. Furthermore, increasing lateral stress linearly increases the tensile strength. This was also confirmed by molecular dynamics simulations employing Embedded Atom Method (EAM) potential. The molecular dynamics simulations also revealed that the thermal vibrations significantly decrease the tensile strength.

Keywords

Fe-Al; superalloys; order; tensile strength; elasticity; ab initio; stability; nanocomposite

Authors

ŠESTÁK, P.; FRIÁK, M.; HOLEC, D.; VŠIANSKÁ, M.; ŠOB, M.

Released

24. 10. 2018

Publisher

MDPI

Location

St. Alban-Anlage 66, 4052 Basel, Switzerland

ISBN

2079-4991

Periodical

Nanomaterials

Year of study

8

Number

11

State

Swiss Confederation

Pages from

873

Pages to

872

Pages count

20

URL

https://www.mdpi.com/2079-4991/8/11/873

Full text in the Digital Library

http://hdl.handle.net/11012/137245

BibTex

@article{BUT151452,
  author="Petr {Šesták} and Martin {Friák} and David {Holec} and Monika {Všianská} and Mojmír {Šob}",
  title="Strength and Brittleness of Interfaces in Fe-Al Superalloy Nanocomposites under Multiaxial Loading: An ab initio and Atomistic Study",
  journal="Nanomaterials",
  year="2018",
  volume="8",
  number="11",
  pages="873--872",
  doi="10.3390/nano8110873",
  issn="2079-4991",
  url="https://www.mdpi.com/2079-4991/8/11/873"
}