Asymmetric distribution of martensitic variants in non-modulated NiMnGa single crystals
Abstract
A strong asymmetric distribution of martensitic variants in non-modulated NiMnGa single crystals with respect to austenite is produced during martensitic transformation. A cubic-to-tetragonal transformation occurs with 24 possible variants divided into two groups. The first group with a misorientation of about 6° is composed of the so-called major variants separated by inter-plate boundaries, while the latter comprises minor variants with misorientation of 12.2°. The 6° rotation associated with major variants can also be observed at each inclination point where conjugation boundaries (CBs) occurs. The removal of CBs straightens out the inclined inter-plate boundaries confirming the Müllner–King mechanism.
Keywords
Austenite Martensite Martensitic Transformation Shape Memory Alloy Orientation RelationshipNotes
Acknowledgements
The work was carried out within the Homing Plus Program (Project 2013-8/3) of Foundation for Polish Science, co-financed from European Union, Regional Development Fund. The financial support by the Ministry of Science and Higher Education of Poland within the Project No. 0063/IP2/2015/73 is also acknowledged.
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