Plasticity evolution in nanoscale Cu/Nb single-crystal multilayers as revealed by synchrotron X-ray microdiffraction

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:635

Article

Budiman, A. S.^1,2  Narayanan, Karthic R.¹  Li, N.²  Wang, J.³  Tamura, N.⁴  Kunz, M.⁴  Misra, A.^2,5 

[1] Singapore Univ Technol & Design, Singapore 138682, Singapore

[2] Los Alamos Natl Lab, Ctr Integrated Nanotechnol CINT, Los Alamos, NM 87545 USA

[3] Los Alamos Natl Lab, MST 8, Los Alamos, NM 87545 USA

[4] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA

[5] Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA

关键词: Single crystal;    Nanolayers;    Incoherent interface;    Pillar compression;    Peak broadening;    Dislocation saturation;   

DOI  :  10.1016/j.msea.2015.03.067

来源: Elsevier

【 摘 要 】

In this study, the evolution of dislocation densities during compressive deformation of nanoscale Cu/Nb single crystal multilayers with individual layer thickness of 20 nm is investigated using Synchrotron X-ray micro-diffraction. The samples were subjected to successive compression straining up to a final cumulative strain of 35%. The nanolayer composite exhibited a maximum flow strength of similar to 1.6 GPa at approximately 24% compressive strain. Synchrotron X-ray micro-diffraction experiments, using a monochromatic beam of 10 keV energy were performed after each compression strain increment. We observed a significant increase in X-ray ring width peak broadening in both Cu and Nb layers up to strains of similar to 3.5% followed by saturation broadening at higher strains. This observation indicates that the interfaces of the Cu/Nb nanolayers are very effective in trapping and annihilating dislocation content during mechanical deformation. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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