Adaptive modulations of martensites

0348782 - FZÚ 2011 RIV US eng J - Journal Article
Kaufmann, S. - Roßler, U.K. - Heczko, Oleg - Wuttig, M. - Buschbeck, J. - Schultz, L. - Fähler, S.
Adaptive modulations of martensites.
Physical Review Letters. Roč. 104, č. 14 (2010), 145702/1-145702/4. ISSN 0031-9007. E-ISSN 1079-7114
Institutional research plan: CEZ:AV0Z10100520
Keywords : adaptive concept of modulated martensite * martensitic Ni-Mn-Ga films * austenite * 14M martensite
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 7.621, year: 2010
http://link.aps.org/doi/10.1103/PhysRevLett.104.145702

Modulated phases occur in numerous functional materials like giant ferroelectrics and magnetic shape memory alloys. To understand the origin of these phases, we employ and generalize the concept of adaptive martensite. As a starting point, we investigate the coexistence of austenite, adaptive 14M phase, and tetragonal martensite in Ni-Mn-Ga magnetic shape-memory alloy epitaxial films. We show that the modulated martensite can be constructed from nanotwinned variants of the tetragonal martensite phase. By combining the concept of adaptive martensite with branching of twin variants, we can explain key features of modulated phases from a microscopic view. This includes metastability, the sequence of 6M- 10M-14M-NM intermartensitic transitions, and the magnetocrystalline anisotropy.
Permanent Link: http://hdl.handle.net/11104/0189212