Effect of microstructural heterogeneity on the mechanical behavior of nanocrystalline metal films

Jagannathan Rajagopalan, M. Taher A. Saif

Research output: Contribution to journalArticle

Abstract

Conventionally, mean grain size is considered the most critical microstructural parameter in determining the mechanical behavior of pure metals. By systematically controlling the distribution of grain orientations in aluminum films, we show that microstructural heterogeneity alone induces large variation in the mechanical behavior of nanocrystalline metal films. Aluminum films with relatively homogeneous microstructure (all grains with identical out-of-plane orientation) show substantially less early Bauschinger effect compared to films with heterogeneous microstructure, irrespective of film thickness or grain size. On the other hand, the films with homogeneous microstructure show relatively higher yield stresses. A direct correspondence is found between the nonuniformity of plastic deformation and early Bauschinger effect, which confirms the critical role of microstructural heterogeneity.

Original languageEnglish (US)
Pages (from-to)2826-2832
Number of pages7
JournalJournal of Materials Research
Volume26
Issue number22
DOIs
StatePublished - Nov 28 2011

Fingerprint

metal films
Metals
Bauschinger effect
microstructure
Aluminum
grain size
Microstructure
aluminum
nonuniformity
plastic deformation
film thickness
Yield stress
Film thickness
Plastic deformation
metals

Keywords

  • Stress/strain relationship
  • Texture
  • Thin film

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Effect of microstructural heterogeneity on the mechanical behavior of nanocrystalline metal films. / Rajagopalan, Jagannathan; Saif, M. Taher A.

In: Journal of Materials Research, Vol. 26, No. 22, 28.11.2011, p. 2826-2832.

Research output: Contribution to journalArticle

@article{3268bb2454a44d4292aab97e34061c50,
title = "Effect of microstructural heterogeneity on the mechanical behavior of nanocrystalline metal films",
abstract = "Conventionally, mean grain size is considered the most critical microstructural parameter in determining the mechanical behavior of pure metals. By systematically controlling the distribution of grain orientations in aluminum films, we show that microstructural heterogeneity alone induces large variation in the mechanical behavior of nanocrystalline metal films. Aluminum films with relatively homogeneous microstructure (all grains with identical out-of-plane orientation) show substantially less early Bauschinger effect compared to films with heterogeneous microstructure, irrespective of film thickness or grain size. On the other hand, the films with homogeneous microstructure show relatively higher yield stresses. A direct correspondence is found between the nonuniformity of plastic deformation and early Bauschinger effect, which confirms the critical role of microstructural heterogeneity.",
keywords = "Stress/strain relationship, Texture, Thin film",
author = "Jagannathan Rajagopalan and Saif, {M. Taher A.}",
year = "2011",
month = "11",
day = "28",
doi = "10.1557/jmr.2011.316",
language = "English (US)",
volume = "26",
pages = "2826--2832",
journal = "Journal of Materials Research",
issn = "0884-2914",
publisher = "Materials Research Society",
number = "22",

}

TY - JOUR

T1 - Effect of microstructural heterogeneity on the mechanical behavior of nanocrystalline metal films

AU - Rajagopalan, Jagannathan

AU - Saif, M. Taher A.

PY - 2011/11/28

Y1 - 2011/11/28

N2 - Conventionally, mean grain size is considered the most critical microstructural parameter in determining the mechanical behavior of pure metals. By systematically controlling the distribution of grain orientations in aluminum films, we show that microstructural heterogeneity alone induces large variation in the mechanical behavior of nanocrystalline metal films. Aluminum films with relatively homogeneous microstructure (all grains with identical out-of-plane orientation) show substantially less early Bauschinger effect compared to films with heterogeneous microstructure, irrespective of film thickness or grain size. On the other hand, the films with homogeneous microstructure show relatively higher yield stresses. A direct correspondence is found between the nonuniformity of plastic deformation and early Bauschinger effect, which confirms the critical role of microstructural heterogeneity.

AB - Conventionally, mean grain size is considered the most critical microstructural parameter in determining the mechanical behavior of pure metals. By systematically controlling the distribution of grain orientations in aluminum films, we show that microstructural heterogeneity alone induces large variation in the mechanical behavior of nanocrystalline metal films. Aluminum films with relatively homogeneous microstructure (all grains with identical out-of-plane orientation) show substantially less early Bauschinger effect compared to films with heterogeneous microstructure, irrespective of film thickness or grain size. On the other hand, the films with homogeneous microstructure show relatively higher yield stresses. A direct correspondence is found between the nonuniformity of plastic deformation and early Bauschinger effect, which confirms the critical role of microstructural heterogeneity.

KW - Stress/strain relationship

KW - Texture

KW - Thin film

UR - http://www.scopus.com/inward/record.url?scp=82055203054&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=82055203054&partnerID=8YFLogxK

U2 - 10.1557/jmr.2011.316

DO - 10.1557/jmr.2011.316

M3 - Article

AN - SCOPUS:82055203054

VL - 26

SP - 2826

EP - 2832

JO - Journal of Materials Research

JF - Journal of Materials Research

SN - 0884-2914

IS - 22

ER -