Structure and microstructure of Ni-Mn-Ga single crystal exhibiting magnetic shape memory effect analysed by high resolution X-ray diffraction

0467511 - FZÚ 2017 RIV GB eng J - Článek v odborném periodiku
Heczko, Oleg - Cejpek, P. - Drahokoupil, Jan - Holý, V.
Structure and microstructure of Ni-Mn-Ga single crystal exhibiting magnetic shape memory effect analysed by high resolution X-ray diffraction.
Acta Materialia. Roč. 115, Aug (2016), s. 250-258. ISSN 1359-6454. E-ISSN 1873-2453
Grant CEP: GA ČR GA13-30397S; GA ČR GA15-00262S
Institucionální podpora: RVO:68378271
Klíčová slova: magnetic field-induced strain * magnetic shape memory effect * X-ray diffraction * structure of Ni-Mn-Ga
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 5.301, rok: 2016

Subtle changes of (micro-) structure can have far-reaching consequences for magnetic shape memory (MSM) effect, also called magnetic induced reorientation (MIR). Detailed X-ray structure analysis using reciprocal mapping of Ni-Mn-Ga single crystals exhibiting MIR at room temperature and prepared in
single macrotwin orientation revealed 10M modulated structure. It indicated that the modulation was
harmonic, i.e. commensurate, but it also showed that the difference when compared to noncommensurate mode or even to adaptive model was very small. The distinction between commensurate and non-commensurate modulation could not be reliably resolved due to large broadening of diffraction peaks. The broadening was caused by small size (less than 100 nm) of structurally coherent L21 ordered domains. The small size of these coherent domains is a result of large concentration of antiphase boundaries.
Trvalý link: http://hdl.handle.net/11104/0265608