Journal
ACTA MATERIALIA
Volume 59, Issue 9, Pages 3390-3397Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.actamat.2011.02.014
Keywords
Ni-Mn-Ga alloys; Orientation relationship; Electron backscatter diffraction (EBSD); Modulated martensite; Twin interface
Funding
- National Natural Science Foundation of China [50820135101]
- Ministry of Education of China [707017, 2007B35, IRT0713]
- Fundamental Research Funds for the Central Universities of China [N090602002]
- CNRS of France [4164]
- Chinese-French project OPTIMAG [ANR-09-BLAN-0382]
Ask authors/readers for more resources
For Ni-Mn-Ga ferromagnetic shape memory alloys, the characteristic features of modulated martensite (including the number/shape of constituent variants, the inter-variant orientation relationship and the geometrical distribution of variant interfaces) determine the attainability of the shape memory effect. In the present work, a comprehensive microstructural and crystallographic investigation has been conducted on a bulk polycrystalline Ni50Mn28Ga22 alloy. As a first attempt, the orientation measurements by electron backscatter diffraction (EBSD) - using the precise information on the commensurate 5M modulated monoclinic superstructure (instead of the conventionally simplified non-modulated tetragonal structure) - were successfully performed to identify the crystallographic orientations on an individual basis. Consequently, the morphology of modulated martensite, the orientation relationships between adjacent variants and the characters of twin interfaces were unambiguously determined. With the thus-obtained full-featured image on the configuration of martensitic variants, the possibility of microstructural modification by proper mechanical training was further discussed. This new effort makes it feasible to explore the crystallographic/microstructural correlations in modulated martensite with high statistical reliability, which in turn provides useful guidance for optimizing the microstructure and shape memory performance. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available