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Title: Mechanical properties of metal-ceramic nanolaminates: Effect of constraint and temperature

Abstract

Al/SiC nanolaminates with equal nominal thicknesses of the Al and SiC layers (10, 25, 50 and 100 nm) were manufactured by magnetron sputtering. The mechanical properties were measured at 25 °C and 100 °C by means of nanoindentation and micropillar compression tests and the deformation mechanisms were analyzed by in situ micropillar compression tests in the transmission electron microscope. In addition, finite element simulations of both tests were carried out to ascertain the role played by the strength of the Al layers and by the elastic constraint of the ceramic layers on the plastic flow of Al in the mechanical response. It was found that the mechanical response was mainly controlled by the constraint during nanoindentation or micropillar compression tests of very thin layered (≈10 nm) laminates, while the influence of the strength of Al layers was not as critical. This behavior was reversed, however, for thick layered laminates (100 nm). Here, these mechanisms point to the different effects of layer thickness during nanoindentation and micropillar compression, at both temperatures, and showed the critical role played by constraint on the mechanical response of nanolaminates made of materials with a very large difference in the elasto-plastic properties.

Authors:
 [1];  [2]; ORCiD logo [3]; ORCiD logo [3]; ORCiD logo [3];  [2]; ORCiD logo [4];  [1]
  1. IMDEA Materials Institute, Madrid (Spain); Polytechnic Univ. of Madrid/Univ. Politecnica de Madrid, Madrid (Spain)
  2. Arizona State Univ., Tempe, AZ (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. IMDEA Materials Institute, Madrid (Spain)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1417175
Report Number(s):
LA-UR-17-28798
Journal ID: ISSN 1359-6454; TRN: US1801004
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Acta Materialia
Additional Journal Information:
Journal Volume: 142; Journal Issue: C; Journal ID: ISSN 1359-6454
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Micropillar compression; Nanoindentation; Composites; Nanolaminates

Citation Formats

Yang, Ling Wei, Mayer, Carl, Li, Nan, Baldwin, Jon Kevin Scott, Mara, Nathan Allan, Chawla, Nikhilesh, Molina-Aldareguia, Jon M., and Llorca, Javier. Mechanical properties of metal-ceramic nanolaminates: Effect of constraint and temperature. United States: N. p., 2017. Web. doi:10.1016/j.actamat.2017.09.042.
Yang, Ling Wei, Mayer, Carl, Li, Nan, Baldwin, Jon Kevin Scott, Mara, Nathan Allan, Chawla, Nikhilesh, Molina-Aldareguia, Jon M., & Llorca, Javier. Mechanical properties of metal-ceramic nanolaminates: Effect of constraint and temperature. United States. doi:10.1016/j.actamat.2017.09.042.
Yang, Ling Wei, Mayer, Carl, Li, Nan, Baldwin, Jon Kevin Scott, Mara, Nathan Allan, Chawla, Nikhilesh, Molina-Aldareguia, Jon M., and Llorca, Javier. Thu . "Mechanical properties of metal-ceramic nanolaminates: Effect of constraint and temperature". United States. doi:10.1016/j.actamat.2017.09.042.
@article{osti_1417175,
title = {Mechanical properties of metal-ceramic nanolaminates: Effect of constraint and temperature},
author = {Yang, Ling Wei and Mayer, Carl and Li, Nan and Baldwin, Jon Kevin Scott and Mara, Nathan Allan and Chawla, Nikhilesh and Molina-Aldareguia, Jon M. and Llorca, Javier},
abstractNote = {Al/SiC nanolaminates with equal nominal thicknesses of the Al and SiC layers (10, 25, 50 and 100 nm) were manufactured by magnetron sputtering. The mechanical properties were measured at 25 °C and 100 °C by means of nanoindentation and micropillar compression tests and the deformation mechanisms were analyzed by in situ micropillar compression tests in the transmission electron microscope. In addition, finite element simulations of both tests were carried out to ascertain the role played by the strength of the Al layers and by the elastic constraint of the ceramic layers on the plastic flow of Al in the mechanical response. It was found that the mechanical response was mainly controlled by the constraint during nanoindentation or micropillar compression tests of very thin layered (≈10 nm) laminates, while the influence of the strength of Al layers was not as critical. This behavior was reversed, however, for thick layered laminates (100 nm). Here, these mechanisms point to the different effects of layer thickness during nanoindentation and micropillar compression, at both temperatures, and showed the critical role played by constraint on the mechanical response of nanolaminates made of materials with a very large difference in the elasto-plastic properties.},
doi = {10.1016/j.actamat.2017.09.042},
journal = {Acta Materialia},
number = C,
volume = 142,
place = {United States},
year = {Thu Sep 21 00:00:00 EDT 2017},
month = {Thu Sep 21 00:00:00 EDT 2017}
}

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