Superior radiation tolerance has been experimentally examined in nanotwinned metals. The stability of nanotwinned structure under radiation is the key factor for advancing the application of nanotwinned metals for nuclear reactors. We thus performed in situ radiation tests for nanotwinned Cu with various twin thicknesses inside a transmission electron microscope. We found that there is a critical twin thickness (10 nm), below which, radiation induced detwinning is primarily accomplished through migration of incoherent twin boundaries. Detwinning is faster for thinner twins in this range, while thicker twins are more stable.
Bibliographical noteFunding Information:
We acknowledge financial support by NSF-DMR-Metallic Materials and Nanostructures Program under grant no. 1643915 . HW acknowledges the funding support for the U.S. Office Naval Research ( N00014-16-1-2778 ). The electron microscopy with in situ ion irradiation was accomplished at Argonne National Laboratory at the IVEM-Tandem Facility, a U.S. Department of Energy Facility funded by the DOE Office of Nuclear Energy , operated under Contract No. DE-AC02-06CH11357 by U Chicago, Argonne, LLC. We also acknowledge the use of microscopes at the Microscopy and Imaging Center at Texas A&M University and the DOE Center for Integrated Nanotechnologies managed by Los Alamos National Laboratory.