Crystal structure determination of incommensurate modulated martensite in Ni-Mn-In Hensler alloys

被引：86

作者：

Yan, Haile ^{[1
,2
]}

Zhang, Yudong ^{[2
,3
]}

Xu, Nan ^{[1
]}

Senyshyn, Anatoliy ^{[4
]}

Brokmeier, Heinz-Guenter ^{[5
,6
]}

Esling, Claude ^{[2
,3
]}

Zhao, Xiang ^{[1
]}

Zuo, Liang ^{[1
]}

机构：

[1] Northeastern Univ, Minist Educ, Key Lab Anisotropy & Texture Mat, Shenyang 110819, Peoples R China

[2] Univ Lorraine, CNRS, UMR 7239, LEM3, F-57045 Metz, France

[3] Univ Lorraine, Lab Excellence Design Alloy Met Low mAss Struct D, F-57045 Metz, France

[4] Tech Univ Munich, Forsch Neutronenquelle Heinz Maier Leibnitz FRM 2, D-85747 Garching, Germany

[5] Tech Univ Clausthal, Inst Werkstoffkunde & Werkstofftech, D-38678 Clausthal Zellerfeld, Germany

[6] Helmholtz Zentrum Geesthacht, D-21502 Geesthacht, Germany

来源：

ACTA MATERIALIA | 2015年 / 88卷

基金：

中国国家自然科学基金;

关键词：

Ni-Mn-In alloy; Modulated martensite; Crystal structure; Rietveld method; Superspace theory; SHAPE-MEMORY ALLOYS; STACKING ORDER STRUCTURES; AUGMENTED-WAVE METHOD; PHASE-TRANSFORMATION; ELECTRON-MICROSCOPY; SURFACE MARTENSITE; GA ALLOYS; RIBBONS;

D O I：

10.1016/j.actamat.2015.01.025

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The crystal structure of modulated martensite in Mn-rich off-stoichiometric Ni2Mn1.44In0.56 alloy was determined with high-resolution powder neutron diffraction and synchrotron X-ray diffraction in the frame of (3 + 1)-dimensional superspace theory. The average crystal structure and the modulation wave vector were firstly derived by analyzing the reflection separations induced by the martensitic transformation on the basis of the transformation orientation inheritance. This treatment could be applied to predetermine the modulated structures of materials with displacive structural transformation. The crystal structure of modulated martensite was finally refined by the Rietveld method. Results show that the martensite possesses an incommensurate 6M modulated structure of superspace group I2/m(alpha 0 gamma)00, with lattice parameters a= 4.3919(4) angstrom, b = 5.6202(1) angstrom, c = 4.3315(7) angstrom, and beta = 93.044(1)degrees, and the modulation wave vector q = 0.343(7) c.* The detailed site occupations for extra-Mn atoms with respect to the stoichiometric case were investigated by ab initio calculations. The extra-Mn atoms have a preference to be uniformly dispersed. A threefold layered superstructure in the 3-dimensional space was proposed to approximately describe the incommensurate modulated structure. This 6M superstructure model is considered to be representative for off-stoichiometric Ni-(Co)-Mn-In modulated martensite with martensitic transformation around room temperature. The present study is expected to offer an important basis for reliable crystallographic and microstructural characterizations on Ni-Mn-In alloys, so as to understand the underlying mechanisms of their multifunctional magneto-responsive properties. (c) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：375 / 388

页数：14

共 57 条

[1] Structural and Magnetic Properties of Magnetic Shape Memory Alloy Ni46Mn41In13 under Magnetic Fields [J].