Bitte benutzen Sie diesen Identifier, um auf die Ressource zu verweisen: https://oa.tib.eu/renate/handle/123456789/4372
Dateien zu dieser Publikation:
Datei GrößeFormat 
Kaufmann_2011_New_J._Phys._13_053029.pdf2,11 MBAdobe PDFAnzeigen/Öffnen
Titel: Modulated martensite: Why it forms and why it deforms easily
Autor(en): Kaufmann, S.Niemann, R.Thersleff, T.Rößler, U.K.Heczko, O.Buschbeck, J.Holzapfel, B.Schultz, L.Fähler, S.
Verlagsversion: https://doi.org/10.1088/1367-2630/13/5/053029
URI: https://doi.org/10.34657/1600
https://oa.tib.eu/renate/handle/123456789/4372
Erscheinungsjahr: 2011
Publiziert in: New Journal of Physics, Volume 13
Verlag: Milton Park : Taylor & Francis
Abstract: Diffusionless phase transitions are at the core of the multifunctionality of (magnetic) shape memory alloys, ferroelectrics and multiferroics. Giant strain effects under external fields are obtained in low symmetric modulated martensitic phases. We outline the origin of modulated phases, their connection with tetragonal martensite and consequences owing to their functional properties by analysing the martensitic microstructure of epitaxial Ni–Mn–Ga films from the atomic to the macroscale. Geometrical constraints at an austenite–martensite phase boundary act down to the atomic scale. Hence, a martensitic microstructure of nanotwinned tetragonal martensite can form. Coarsening of twin variants can reduce twin boundary energy, a process we could observe from the atomic to the millimetre scale. Coarsening is a fractal process, proceeding in discrete steps by doubling twin periodicity. The collective defect energy results in a substantial hysteresis, which allows the retention of modulated martensite as a metastable phase at room temperature. In this metastable state, elastic energy is released by the formation of a 'twins within twins' microstructure that can be observed from the nanometre to the millimetre scale. This hierarchical twinning results in mesoscopic twin boundaries. Our analysis indicates that mesoscopic boundaries are broad and diffuse, in contrast to the common atomically sharp twin boundaries of tetragonal martensite. We suggest that the observed extraordinarily high mobility of such mesoscopic twin boundaries originates from their diffuse nature that renders pinning by atomistic point defects ineffective.
Schlagwörter: Atomic scale; Defect energy; Discrete step; Elastic energy; External fields; Functional properties; Geometrical constraints; Giant strain; High mobility; Macro scale; Martensitic microstructure; Martensitic phasis; Mesoscopics; Meta-stable state; Metastable phase; Modulated phasis; Multiferroics; Multifunctionality; Nanometres; Ni-Mn-GaRoom temperature; Shape memory alloy; Twin boundaries; Twin boundary energy
Publikationstyp: article; Text
Publikationsstatus: publishedVersion
DDC: 530
Lizenz: CC BY-NC-SA 3.0 Unported
Link zur Lizenz: https://creativecommons.org/licenses/by-nc-sa/3.0/
Enthalten in den Sammlungen:Physik

Zur Langanzeige
Kaufmann, S., R. Niemann, T. Thersleff, U.K. Rößler, O. Heczko, J. Buschbeck, B. Holzapfel, L. Schultz and S. Fähler, 2011. Modulated martensite: Why it forms and why it deforms easily. 2011. Milton Park : Taylor & Francis
Kaufmann, S., Niemann, R., Thersleff, T., Rößler, U. K., Heczko, O., Buschbeck, J., Holzapfel, B., Schultz, L. and Fähler, S. (2011) “Modulated martensite: Why it forms and why it deforms easily.” Milton Park : Taylor & Francis. doi: https://doi.org/10.1088/1367-2630/13/5/053029.
Kaufmann S, Niemann R, Thersleff T, Rößler U K, Heczko O, Buschbeck J, Holzapfel B, Schultz L, Fähler S. Modulated martensite: Why it forms and why it deforms easily. Milton Park : Taylor & Francis; 2011.
Kaufmann, S., Niemann, R., Thersleff, T., Rößler, U. K., Heczko, O., Buschbeck, J., Holzapfel, B., Schultz, L., & Fähler, S. (2011). Modulated martensite: Why it forms and why it deforms easily (Version publishedVersion). Version publishedVersion. Milton Park : Taylor & Francis. https://doi.org/https://doi.org/10.1088/1367-2630/13/5/053029
Kaufmann S, Niemann R, Thersleff T, Rößler U K, Heczko O, Buschbeck J, Holzapfel B, Schultz L, Fähler S. Modulated martensite: Why it forms and why it deforms easily. Published online 2011. doi:https://doi.org/10.1088/1367-2630/13/5/053029


Diese Publikation wurde unter der folgenden Lizenz veröffentlicht: Creative-Commons-Lizenz Creative Commons