Evidence of a temperature transition for denuded zone formation in nanocrystalline Fe under He irradiation. Issue 3 (4th May 2017)

• Record Type: Journal Article
• Authors: El-Atwani, O.; Nathaniel, J. E.; Leff, A. C.; Baldwin, J. K.; Hattar, K.; Taheri, M. L.
• Is Part Of: Materials research letters. Volume 5:Issue 3(2017)
• Page Start: 195
• Page End: 200
• Publication Date: 2017-05-04
• Subjects: He implantation -- TEM -- bubbles -- denuded zones -- grain boundary; Materials science -- Research -- Periodicals; Biomedical materials -- Research -- Periodicals; Composite materials -- Research -- Periodicals; Biomedical materials -- Research; Composite materials -- Research; Materials science -- Research; Periodicals; 620.1105
• DOI: 10.1080/21663831.2016.1243591
• Languages: English
• ISSNs: 2166-3831

Abstract

ABSTRACT: Nanocrystalline materials are radiation-tolerant materials' candidates due to their high defect sink density. Here, nanocrystalline iron films were irradiated with 10 keV helium ions in situ in a transmission electron microscope at elevated temperatures. Grain-size-dependent bubble density changes and denuded zone occurrence were observed at 700 K, but not at 573 K. This transition, attributed to increased helium–vacancy migration at elevated temperatures, suggests that nanocrystalline microstructures are more resistant to swelling at 700 K due to decreased bubble density. Finally, denuded zone formation had no correlation with grain size and misorientation angle under the conditions studied. GRAPHICAL ABSTRACT: IMPACT STATEMENT Denuded zone formation and bubble density/swelling vs. grain size trends were shown to occur over a threshold temperature in helium-irradiated nanocrystalline iron.