Stability of incommensurately modulated Ni.sub.50./sub.Mn.sub.27./sub.Ga.sub.22./sub.Fe.sub.1./sub. 10M martensite under uniaxial tensile stress

0584863 - FZÚ 2025 RIV GB eng J - Článek v odborném periodiku
Vinogradova, M. - Sozinov, A. - Straka, Ladislav - Veřtát, Petr - Heczko, Oleg - Zelený, M. - Chulist, R. - Ullakko, K.
Stability of incommensurately modulated Ni₅₀Mn₂₇Ga₂₂Fe₁ 10M martensite under uniaxial tensile stress.
Scripta Materialia. Roč. 247, July (2024), č. článku 116096. ISSN 1359-6462. E-ISSN 1872-8456
Grant CEP: GA ČR(CZ) GA21-06613S; GA MŠMT(CZ) EF18_053/0016627; GA MŠMT(CZ) EH22_008/0004591
Institucionální podpora: RVO:68378271
Klíčová slova: magnetic shape memory * Ni-Mn-Ga * X-ray diffraction * incommensurately modulated crystal structure
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 6, rok: 2022
Způsob publikování: Open access

We investigate the incommensurately modulated crystal structure in the Ni50Mn27Ga22Fe1 magnetic shape memory alloy. We focus on temperature- and stress-induced changes, particularly measuring the a and b lattice parameters and the monoclinic angle. The in-situ XRD experiment shows that the thermally-induced commensurate-incommensurate (C-IC) transition coincides with the change of the average lattice symmetry from monoclinic to orthorhombic. The thermally-induced IC structure is stable under uniaxial tensile stress along the a-axis for deformation ε < 0.8 %. A mixture of the IC and C structures appears for ε > 0.8 % and the changes become irreversible. The volume fraction of the C structure further increases with increasing deformation. These results provide vital initial insights into the structural evolution of Ni-Mn-Ga alloys and enable us to establish the role of C and IC structures in their extraordinarily high mobility of twin boundaries.
Trvalý link: https://hdl.handle.net/11104/0352688