Detail publikace

Shear Deformation of Non-modulated Ni2MnGa Martensite: An Ab Initio Study

HECZKO, M. ŠESTÁK, P. SEINER, H. ZELENÝ, M.

Anglický název

Shear Deformation of Non-modulated Ni2MnGa Martensite: An Ab Initio Study

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

en

Originální abstrakt

The impact of shear deformation in (101)[101] system of non-modulated (NM) martensite in Ni2MnGa ferromagnetic shape memory alloy is investigated by means of ab initio atomistic simulations. The shear system is associated with twinning of NM lattice and intermatensitic transformation to modulated structures. The stability of the NM lattice increases with increasing content of Mn. The most realistic shear mechanism for twin reorientation can be approximated by the simple shear mechanism, although the lowest barriers were calculated for pure shear mechanism. The energy barrier between twin variants further reduces due to spontaneous appearance of lattice modulation or, in other words, the nanotwins with thickness of two atomic planes. Such nanotwins appear also on the generalized planar fault energy (GPFE) curve calculated using a newly developed advanced procedure and exhibits even lower energy than the defect free NM structure. These nanotwin doublelayers are also basic building blocks of modulated structures and play an important role in intermartensitic transformation.

Anglický abstrakt

The impact of shear deformation in (101)[101] system of non-modulated (NM) martensite in Ni2MnGa ferromagnetic shape memory alloy is investigated by means of ab initio atomistic simulations. The shear system is associated with twinning of NM lattice and intermatensitic transformation to modulated structures. The stability of the NM lattice increases with increasing content of Mn. The most realistic shear mechanism for twin reorientation can be approximated by the simple shear mechanism, although the lowest barriers were calculated for pure shear mechanism. The energy barrier between twin variants further reduces due to spontaneous appearance of lattice modulation or, in other words, the nanotwins with thickness of two atomic planes. Such nanotwins appear also on the generalized planar fault energy (GPFE) curve calculated using a newly developed advanced procedure and exhibits even lower energy than the defect free NM structure. These nanotwin doublelayers are also basic building blocks of modulated structures and play an important role in intermartensitic transformation.

Klíčová slova anglicky

NiMnGa; Ferromagnetic shape memory alloy; Martensite; Twinning; Shear deformation; Intermartensitic transformation; Ab initio calculations

Vydáno

07.11.2024

Nakladatel

SPRINGER INT PUBL AG

Místo

CHAM

ISSN

2199-3858

Ročník

10

Číslo

4

Strany od–do

474–486

Počet stran

13

BIBTEX


@article{BUT193835,
  author="Martin {Heczko} and Petr {Šesták} and Hanuš {Seiner} and Martin {Zelený},
  title="Shear Deformation of Non-modulated Ni2MnGa Martensite: An Ab Initio Study",
  year="2024",
  volume="10",
  number="4",
  month="November",
  pages="474--486",
  publisher="SPRINGER INT PUBL AG",
  address="CHAM",
  issn="2199-3858"
}