Magnetic shape memory effect in Ni-Mn-Ga single crystal

0467349 - FZÚ 2017 RIV CH eng C - Konferenční příspěvek (zahraniční konf.)
Heczko, Oleg - Kopecký, Vít - Drahokoupil, Jan - Vronka, Marek - Perevertov, Oleksiy - Kopeček, Jaromír
Magnetic shape memory effect in Ni-Mn-Ga single crystal.
Materials Science Forum, vol. 879. Pfaffikon:: Trans Tech Publications Inc., 2016 - (Ionescu, M.; Mishra, B.; Kozeschnik, E.; Sommitsch, C.; Chandra, T.), s. 738-743. ISBN 978-303571129-5. ISSN 0255-5476.
[9th International Conference on Processing and Manufacturing of Advanced Materials, THERMEC 2016. Graz (AT), 29.05.2016-03.06.2016]
Grant CEP: GA MŠMT LO1409; GA MŠMT LM2015088; GA ČR GA15-00262S
Institucionální podpora: RVO:68378271
Klíčová slova: magnetic shape memory effect * magnetically-induced reorientation * ferromagnetic shape memory alloy * Ni-Mn-Ga * modulated martensite * twin boundary
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus

Magnetic shape memory effect is general name for several effects in which the most visible feature is huge strain induced by magnetic field. Magnetic field-induced structure reorientation (MIR) occurs due to motion of twin boundaries in single phase. As the magnetic field is a relatively weak force compared with mechanical stress, very high mobility of twin boundaries is crucial. Here we study the properties of martensite relevant for this effect using X-ray diffraction, optical and electron microscopy, magnetic observation and mechanical testing. In 10M modulated martensite, two types of mobile twin boundary (type I and type II) are observed with complex layered microstructures consisting of a hierarchy of twinning systems. We search for analogue with non-magnetic Cu-Ni-Al shape memory alloy.
Trvalý link: http://hdl.handle.net/11104/0266632