9R phase enabled superior radiation stability of nanotwinned Cu alloys via in situ radiation at elevated temperature

Authors

Cuncai Fan, Purdue University
Dongyue Xie, University of Nebraska-LincolnFollow
Jin Li, Purdue University
Zhongxia Shang, Purdue University
Youxing Chen, University of North Carolina, CharlotteFollow
Sichuang Xue, Purdue University
Jian Wang, University of Nebraska-LincolnFollow
Meimei Li, Argonne National LaboratoryFollow
Anter El-Azab, Purdue UniversityFollow
Haiyan Wang, Purdue UniversityFollow
Xinghang Zhang, Purdue UniversityFollow

Document Type

Article

Date of this Version

2019

Citation

Published in Acta Materialia 167 (2019), pp 248–256.

doi 10.1016/j.actamat.2019.01.037

Comments

Copyright © 2019; published by Elsevier Ltd on behalf of Acta Materialia Inc. Used by permission.

Abstract

Nanotwinned metals exhibit outstanding radiation tolerance as twin boundaries effectively engage, transport and eliminate radiation-induced defects. However, radiation-induced detwinning may reduce the radiation tolerance associated with twin boundaries, especially at elevated temperatures. Here we show, via in-situ Kr ion irradiation inside a transmission electron microscope, that 3 at. % Fe in epitaxial nanotwinned Cu (Cu₉₇Fe₃) significantly improves the thermal and radiation stability of nanotwins during radiation up to 5 displacements-per-atom at 200 °C. Such enhanced stability of nanotwins is attributed to a diffuse 9R phase resulted from the dissociation of incoherent twin boundaries in nanotwinned Cu₉₇Fe₃. The mechanisms for the enhanced stability of twin boundaries in irradiated nanotwinned alloys are discussed. The stabilization of nano-twins opens up opportunity for the application of nanotwinned alloys for aggressive radiation environments.

Includes supplemental Appendix.

Video files are attached below.