Ab initio study of properties of Co- and Cu- doped Ni-Mn-Ga alloys

conference paper

English

The influence of Co and Cu doping on Ni-Mn-Ga alloy is investigated using the first-principles exact muffin-tin orbital method in combination with the coherent-potential approximation. The energy difference between the austenite (A) and the nonmodulated (NM) martensite ΔE_A-NM depends linearly on the Cu concentration and distribution, with a minimum for all Cu at Mn sites and a maximum for all Cu at Ga sites. For alloys simultaneously doped by Co in Ni sublattice and Cu in Mn or Ga sublattice, the effects of the individual dopants on ΔE_A-NM and (c/a)_NM and are almost independent. The alloy with composition Ni46Co4Mn24Ga22Cu4 exhibits decreased equilibrium (c/a)_NM and increased ΔE_A-NM in comparison with Ni50Mn25Ga25, which is in agreement with the previous experimental results.

Magnetic shape memory alloys; martensitic phase transitions; tetragonal deformation; ab initio calculations;

ZELENÝ, M.; SOZINOV, A.; BJÖRKMAN, T.; STRAKA, L.; NIEMINEN, R. M.

2015

6. 11. 2015

Elsevier Ltd.

2214-7853

Materials Today: Proceedings

2

S3

United States of America

S601

S604

4

http://www.sciencedirect.com/science/article/pii/S221478531500601X

http://hdl.handle.net/11012/201043