Deformation twins and related softening behavior in nanocrystalline Cu-30% Zn alloy

Author(s)
Hamet Nicosia Bahmanpour, Khaled M. Youssef, Jelena Horky, Daria Setman, Mark A. Atwater, Michael Zehetbauer, Ronald O. Scattergood, Carl C. Koch
Abstract

Nanocrystalline Cu-30% Zn samples were produced by high energy ball milling at 77 K and room temperature. Cryomilled flakes were further processed by ultrahigh strain high pressure torsion (HPT) or room temperature milling to produce bulk artifact-free samples. Deformation-induced grain growth and a reduction in twin probability were observed in HPT consolidated samples. Investigations of the mechanical properties by hardness measurements and tensile tests revealed that at small grain sizes of less than similar to 35 nm Cu-30% Zn deviates from the classical Hall-Petch relation and the strength of nanocrsytalline Cu-30% Zn is comparable with that of nanocrystalline pure copper. High resolution transmission electron microscopy studies show a high density of finely spaced deformation nanotwins, formed due to the low stacking fault energy of 14 mJ m-2 and low temperature severe plastic deformation. Possible softening mechanisms proposed in the literature for nanotwin copper are addressed and the twin-related softening behavior in nanotwinned Cu is extended to the Cu-30% Zn alloy based on detwinning mechanisms.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
North Carolina State University
Journal
Acta Materialia
Volume
60
Pages
3340-3349
No. of pages
10
ISSN
1359-6454
DOI
https://doi.org/10.1016/j.actamat.2012.02.036
Publication date
2012
Peer reviewed
Yes
Austrian Fields of Science 2012
210006 Nanotechnology, 103018 Materials physics
Portal url
https://ucrisportal.univie.ac.at/en/publications/deformation-twins-and-related-softening-behavior-in-nanocrystalline-cu30-zn-alloy(145852e9-c315-4139-b5e3-6b3649fb70d4).html