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Title: Synchrotron high energy X-ray diffraction study of microstructure evolution of severely cold drawn NiTi wire during annealing

Abstract

Microstructure evolution of a cold-drawn NiTi shape memory alloy wire was investigated by means of in-situ synchrotron high-energy X-ray diffraction during continuous heating. The cold-drawn wire contained amorphous regions and nano-crystalline domains in its microstructure. Pair distribution function analysis revealed that the amorphous regions underwent structural relaxation via atomic rearrangement when heated above 100 °C. The nano-crystalline domains were found to exhibit a strong cold work induced lattice strain anisotropy having a preferential <111> fiber orientation along the wire axial direction. The lattice strain anisotropy systematically decreased upon heating above 200 °C, implying a structural recovery. A broad conical texture was formed in the wire specimen after crystallization similar in detail to the initial <111> texture axial orientation of the nano-crystalline domains produced by the severe cold wire drawing deformation.

Authors:
ORCiD logo; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
National Natural Science Foundation of China (NNSFC); National Basic Research Program of China; Australian Research Council; Northern Illinois University - Institute for Nanoscience, Engineering and Technology; USDOE Office of Science - Office of Basic Energy Sciences - Scientific User Facilities Division
OSTI Identifier:
1390813
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta Materialia; Journal Volume: 115; Journal Issue: C
Country of Publication:
United States
Language:
English
Subject:
crystallization; in-situ synchrotron high energy X ray diffraction; shape memory alloy; structural relaxation

Citation Formats

Yu, Cun, Aoun, Bachir, Cui, Lishan, Liu, Yinong, Yang, Hong, Jiang, Xiaohua, Cai, Song, Jiang, Daqiang, Liu, Zunping, Brown, Dennis E., and Ren, Yang. Synchrotron high energy X-ray diffraction study of microstructure evolution of severely cold drawn NiTi wire during annealing. United States: N. p., 2016. Web. doi:10.1016/j.actamat.2016.05.039.
Yu, Cun, Aoun, Bachir, Cui, Lishan, Liu, Yinong, Yang, Hong, Jiang, Xiaohua, Cai, Song, Jiang, Daqiang, Liu, Zunping, Brown, Dennis E., & Ren, Yang. Synchrotron high energy X-ray diffraction study of microstructure evolution of severely cold drawn NiTi wire during annealing. United States. doi:10.1016/j.actamat.2016.05.039.
Yu, Cun, Aoun, Bachir, Cui, Lishan, Liu, Yinong, Yang, Hong, Jiang, Xiaohua, Cai, Song, Jiang, Daqiang, Liu, Zunping, Brown, Dennis E., and Ren, Yang. 2016. "Synchrotron high energy X-ray diffraction study of microstructure evolution of severely cold drawn NiTi wire during annealing". United States. doi:10.1016/j.actamat.2016.05.039.
@article{osti_1390813,
title = {Synchrotron high energy X-ray diffraction study of microstructure evolution of severely cold drawn NiTi wire during annealing},
author = {Yu, Cun and Aoun, Bachir and Cui, Lishan and Liu, Yinong and Yang, Hong and Jiang, Xiaohua and Cai, Song and Jiang, Daqiang and Liu, Zunping and Brown, Dennis E. and Ren, Yang},
abstractNote = {Microstructure evolution of a cold-drawn NiTi shape memory alloy wire was investigated by means of in-situ synchrotron high-energy X-ray diffraction during continuous heating. The cold-drawn wire contained amorphous regions and nano-crystalline domains in its microstructure. Pair distribution function analysis revealed that the amorphous regions underwent structural relaxation via atomic rearrangement when heated above 100 °C. The nano-crystalline domains were found to exhibit a strong cold work induced lattice strain anisotropy having a preferential <111> fiber orientation along the wire axial direction. The lattice strain anisotropy systematically decreased upon heating above 200 °C, implying a structural recovery. A broad conical texture was formed in the wire specimen after crystallization similar in detail to the initial <111> texture axial orientation of the nano-crystalline domains produced by the severe cold wire drawing deformation.},
doi = {10.1016/j.actamat.2016.05.039},
journal = {Acta Materialia},
number = C,
volume = 115,
place = {United States},
year = 2016,
month = 8
}
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