Publication detail

Transformation Paths from Cubic to Low-Symmetry Structures in Heusler Ni2MnGa Compound

ZELENÝ, M. STRAKA, L. SOZINOV, A. HECZKO, O.

Original Title

Transformation Paths from Cubic to Low-Symmetry Structures in Heusler Ni2MnGa Compound

Type

journal article in Web of Science

Language

English

Original Abstract

In order to explain the formation of low-temperature phases in stoichiometric Ni2MnGa magnetic shape memory alloy, we investigate the phase transformation paths from cubic austenite with Heusler structure to low-symmetry martensitic structures. We used ab initio calculations combined with the generalized solid state nudged elastic band method to determine the minimum energy path and corresponding changes in crystal lattice. The four-, five-, and seven-layered modulated phases of martensite (4O, 10M, and 14M) are built as the relaxed nanotwinned non-modulated (NM) phase. Despite having a total energy larger than the other martensitic phases, the 10M phase will spontaneously form at 0 K, because there is no energy barrier on the path and the energy decreases with a large negative slope. Moreover, a similar negative slope in the beginning of path is found also for the transformation to the 6M premartensite, which appears as a local minimum on the path leading further to 10M martensite. Transformation paths to other structures exhibit more or less significant barriers in the beginning hindering such a transformation from austenite. These findings correspond to experiment and demonstrates that the kinetics of the transformation is decisive for the selection of the particular low-symmetry structure.

Keywords

Magnetic shape memory alloy, martensitic transformation, ab initio calculation

Authors

ZELENÝ, M.; STRAKA, L.; SOZINOV, A.; HECZKO, O.

Released

8. 5. 2018

Publisher

Springer Nature

ISBN

2045-2322

Periodical

Scientific Reports

Year of study

8

Number

1

State

United Kingdom of Great Britain and Northern Ireland

Pages from

1

Pages to

8

Pages count

8

URL

Full text in the Digital Library

BibTex

@article{BUT147302,
  author="Martin {Zelený} and Ladislav {Straka} and Alexei {Sozinov} and Oleg {Heczko}",
  title="Transformation Paths from Cubic to Low-Symmetry Structures in Heusler Ni2MnGa Compound",
  journal="Scientific Reports",
  year="2018",
  volume="8",
  number="1",
  pages="1--8",
  doi="10.1038/s41598-018-25598-z",
  issn="2045-2322",
  url="https://www.nature.com/articles/s41598-018-25598-z"
}