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Title: The relationship between indentation and uniaxial creep in amorphous selenium

Abstract

Ultralow load indentation techniques can be used to obtain time-dependent mechanical properties, termed indentation creep, of materials. However, the comparison of indentation creep data to that obtained during conventional creep testing is difficult, mainly due to the determination of the strain rate experienced by the material during indentation. Using the power-law creep equation and the equation for Newtonian viscosity as a function of stress and strain rate, a relationship between indentation strain rate,{center_dot}{epsilon}{sub {ital l}}={ital @};Dh/{ital h}, and the effective strain rate occurring during the indentation creep process is obtained. Indentation creep measurements on amorphous selenium in the Newtonian viscous flow regime above the glass transition temperature were obtained. The data was then used to determine that the coefficient relating indentation strain rate to the effective strain rate is equal to 0.09, or{center_dot}{epsilon}=0.0{center_dot}{epsilon}{sub {ital l}}.

Authors:
 [1];  [2];  [1]
  1. Department of Materials Science and Engineering, University of Arizona, Tucson, Arizona 85721 (United States)
  2. Nano Instruments, Inc., 1001 Larson Drive, Oak Ridge, Tennessee 37831 (United States)
Publication Date:
Research Org.:
Oak Ridge Institute of Science and Education
OSTI Identifier:
119409
DOE Contract Number:
AC05-76OR00033; AC05-84OR21400
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Materials Research; Journal Volume: 10; Journal Issue: 8; Other Information: PBD: Aug 1995
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; SELENIUM; MECHANICAL PROPERTIES; AMORPHOUS STATE; CREEP; DEFORMATION; HARDNESS; VISCOSITY

Citation Formats

Poisl, W.H., Oliver, W.C., and Fabes, B.D.. The relationship between indentation and uniaxial creep in amorphous selenium. United States: N. p., 1995. Web. doi:10.1557/JMR.1995.2024.
Poisl, W.H., Oliver, W.C., & Fabes, B.D.. The relationship between indentation and uniaxial creep in amorphous selenium. United States. doi:10.1557/JMR.1995.2024.
Poisl, W.H., Oliver, W.C., and Fabes, B.D.. Tue . "The relationship between indentation and uniaxial creep in amorphous selenium". United States. doi:10.1557/JMR.1995.2024.
@article{osti_119409,
title = {The relationship between indentation and uniaxial creep in amorphous selenium},
author = {Poisl, W.H. and Oliver, W.C. and Fabes, B.D.},
abstractNote = {Ultralow load indentation techniques can be used to obtain time-dependent mechanical properties, termed indentation creep, of materials. However, the comparison of indentation creep data to that obtained during conventional creep testing is difficult, mainly due to the determination of the strain rate experienced by the material during indentation. Using the power-law creep equation and the equation for Newtonian viscosity as a function of stress and strain rate, a relationship between indentation strain rate,{center_dot}{epsilon}{sub {ital l}}={ital @};Dh/{ital h}, and the effective strain rate occurring during the indentation creep process is obtained. Indentation creep measurements on amorphous selenium in the Newtonian viscous flow regime above the glass transition temperature were obtained. The data was then used to determine that the coefficient relating indentation strain rate to the effective strain rate is equal to 0.09, or{center_dot}{epsilon}=0.0{center_dot}{epsilon}{sub {ital l}}.},
doi = {10.1557/JMR.1995.2024},
journal = {Journal of Materials Research},
number = 8,
volume = 10,
place = {United States},
year = {Tue Aug 01 00:00:00 EDT 1995},
month = {Tue Aug 01 00:00:00 EDT 1995}
}
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