Severe plastic deformation (SPD) is a common method to fabricate nano-grained metals. However for Zr, a structural metal for nuclear applications, obtaining a nanoscale grain structure via SPD has been problematic due to deformation twinning and phase transformations. Here, nanostructured hcp Zr is fabricated through a refinement process via the introduction of a biphase interface. Despite mechanical and thermal conditions known to chemically mix Zr and Nb, no intermixing is observed and the heterophase interfaces appear resistant to phase transformations and twinning. Increasing the density of chmically sharp Zr-Nb interfaces is a very different refinement mechanism than substructure development, stacking fault formation, or alloying.
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Acknowledgements JSC and RJM were supported by the Los Alamos National Laboratory Directed Research and Development (LDRD) project 20140348ER. TMP, IJB and NAM wish to acknowledge support by the UC Lab Fees Research Program # UCD-12-0045.15. TN was supported by the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program. Los Alamos National Laboratory is operated by Los Alamos National Security LLC under DOE Contract DEAC52-06NA25396. NeD results were collected on the High Pressure Preferred Orientation (HIPPO) beam line at the Los Alamos Neutron Science Center. Electron microscopy was performed at the Los Alamos Electron Microscopy Laboratory.
This material is published by permission of the Los Alamos National Laboratory, operated by Los Alamos National Security, LLC for the US Department of Energy under Contract No. DE-AC52-06NA25396. The US Government retains for itself, and others acting on its behalf, a paid-up, non-exclusive, and irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government. The work of John S Carpenter, Rod McCabe, Shijian Zheng, Jeffrey Scott, Sven Vogel, Nathan Mara and Irene Beyerlein was authored as part of their official duties as Contractors for the United States Government and is therefore a work of the United States Government. In accordance with 17 USC. 105, no copyright protection is available for such works under US Law. Tom Nizolek and Tresa Pollock hereby waive their right to assert copyright, but not their right to be named as co-authors in the article. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The moral rights of the named author(s) have been asserted.
- Severe plastic deformation