The radiation damage tolerance of ultra-high strength nanolayered composites

Abstract

Interfaces act as obstacles to slip and sinks for radiation-induced defects. Hence, nanolayered composites that contain a large volume fraction of interfaces provide over an order of magnitude increase in strength and enhanced radiation damage tolerance compared to bulk materials. This paper shows the experimental and atomistic modeling results from a Cu-Nb nanolayered composite to highlight the roles of nanostructuring length scales and the response of interfaces to ion collision cascades in designing composite materials with high radiation damage tolerance. A. Misra, M.J. Demkowicz, and R.G. Hoagland are with Los Alamos National Laboratory, Los Alamos, NM, 87545; X. Zhang is now with the Department of Mechanical Engineering, Texas A&M University, College Station, TX. Dr. Misra can be reached at (505) 667-9860; e-mail amisra@lanl.gov.

Structure, shear resistance and interaction with point defects of interfaces in Cu–Nb nanocomposites synthesized by severe plastic deformation

“…We then compare our results to prior work on another type of Cu-Nb interface found in magnetron sputtered composites [6,9,[15][16][17][18][19]. Although these two interfaces have many qualitative structural features in common, they exhibit marked dissimilarities in certain properties.…”

“…Much recent research on novel structural materials aims to exploit the influence of interfaces [2], e.g. to improve wear resistance of electrodeposited nanostructured alloys [3][4][5] or to heal radiation damage in magnetron sputtered nanocomposites [6][7][8][9]. Due to improvements in characterization and modeling techniques, interfaces may now be studied with unprecedented detail and precision [10].…”

Formation, migration, and clustering of delocalized vacancies and interstitials at a solid-state semicoherent interface

“…Interfaces with such properties may therefore absorb defects created in the neighboring layers without becoming damaged themselves. Indeed, interfaces are thought to be responsible for the enhanced radiation damage resistance of Cu-Nb multilayer nanocomposites 13,83 . They are also thought to delay precipitation of implanted He into nanoscale bubbles [84][85][86] .…”

“Bulk” Nanocrystalline Metals: Review of the Current State of the Art and Future Opportunities for Copper and Copper Alloys

“…In truth, this high surface area of interfaces has similarly motivated efforts in Cu-Nb multilayered thin films for radiation resistance. 173,174 Moreover, the atomic structure of the grain boundary has been shown to have an effect on the interaction with point defects. 171,175,176 This fact suggests that increasing the concentration of certain types of boundaries may also be beneficial in radiation resistance of nanocrystalline materials.…”