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Title: Effect of temperature on the nano/microstructure and mechanical behavior of nanotwinned Ag films

Abstract

In situ and ex situ annealed nanotwinned (NT) Ag thin films have been investigated by TEM and tensile testing to reveal the thermal stability of the twin boundaries, grain boundaries, dislocation densities, and their respective influence of the macroscopic yield stress. The NT Ag films synthesized by magnetron sputtering form both coherent (CTB, Σ3{111}) and incoherent (ITB, Σ3{112}) twin boundaries that are thermally stable up to 473 K (200 Celsius), i.e., no obvious changes in grain size, twin spacing, and yield stress. In situ TEM observations show the dislocations become mobile at 453 K (180 Celsius) resulting in dislocation annihilation primarily at twin and grain boundaries. Rotation of grains with low-angle grain boundaries was observed during in situ heating, resulting in the growth of columnar grains above 453 K (180 Celsius). However, no noticeable changes in the spacings of CTBs were observed during the entire in situ and ex situ annealing [up to 873 K (600 Celsius)]. The increase in grain size and concomitant decrease in yield stress following annealing at various temperatures can be described by the Hall-Petch relationship, demonstrating that grain size rather than twin spacing is most sensitive to thermal annealing and plays a dominant role inmore » the deformation of NT Ag films.« less

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. Ames Lab., Ames, IA (United States)
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1221924
Report Number(s):
IS-J-8766
Journal ID: ISSN 1073-5623; PII: 3028
Grant/Contract Number:
AC02-07CH11358
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science
Additional Journal Information:
Journal Volume: 46; Journal Issue: 9; Journal ID: ISSN 1073-5623
Publisher:
ASM International
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; columnar growth; thermostability; twin spacing; dislocation density; yield stress

Citation Formats

Zhang, Huan, Geng, Jie, Ott, Ryan T., Besser, Matthew F., and Kramer, Matthew J. Effect of temperature on the nano/microstructure and mechanical behavior of nanotwinned Ag films. United States: N. p., 2015. Web. doi:10.1007/s11661-015-3028-8.
Zhang, Huan, Geng, Jie, Ott, Ryan T., Besser, Matthew F., & Kramer, Matthew J. Effect of temperature on the nano/microstructure and mechanical behavior of nanotwinned Ag films. United States. doi:10.1007/s11661-015-3028-8.
Zhang, Huan, Geng, Jie, Ott, Ryan T., Besser, Matthew F., and Kramer, Matthew J. Wed . "Effect of temperature on the nano/microstructure and mechanical behavior of nanotwinned Ag films". United States. doi:10.1007/s11661-015-3028-8. https://www.osti.gov/servlets/purl/1221924.
@article{osti_1221924,
title = {Effect of temperature on the nano/microstructure and mechanical behavior of nanotwinned Ag films},
author = {Zhang, Huan and Geng, Jie and Ott, Ryan T. and Besser, Matthew F. and Kramer, Matthew J.},
abstractNote = {In situ and ex situ annealed nanotwinned (NT) Ag thin films have been investigated by TEM and tensile testing to reveal the thermal stability of the twin boundaries, grain boundaries, dislocation densities, and their respective influence of the macroscopic yield stress. The NT Ag films synthesized by magnetron sputtering form both coherent (CTB, Σ3{111}) and incoherent (ITB, Σ3{112}) twin boundaries that are thermally stable up to 473 K (200 Celsius), i.e., no obvious changes in grain size, twin spacing, and yield stress. In situ TEM observations show the dislocations become mobile at 453 K (180 Celsius) resulting in dislocation annihilation primarily at twin and grain boundaries. Rotation of grains with low-angle grain boundaries was observed during in situ heating, resulting in the growth of columnar grains above 453 K (180 Celsius). However, no noticeable changes in the spacings of CTBs were observed during the entire in situ and ex situ annealing [up to 873 K (600 Celsius)]. The increase in grain size and concomitant decrease in yield stress following annealing at various temperatures can be described by the Hall-Petch relationship, demonstrating that grain size rather than twin spacing is most sensitive to thermal annealing and plays a dominant role in the deformation of NT Ag films.},
doi = {10.1007/s11661-015-3028-8},
journal = {Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science},
number = 9,
volume = 46,
place = {United States},
year = {Wed Jun 24 00:00:00 EDT 2015},
month = {Wed Jun 24 00:00:00 EDT 2015}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 10works
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