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Title: Final Report LDRD 04-ERD-021

Abstract

In this project, we performed experiments and simulations to establish constitutive models for plastic behavior and to determine the deformation mechanism of nanocrystalline materials at different grain sizes (<100 nm) and high strain rates (>10{sup 6}/s). The experiments used both laser-induced shocks and isentropic compression to investigate, for the first time, the high-strain-rate deformation of nanocrystalline Ni. Samples were characterized using transmission electron microscopy, nanoindentation, profilometry, and x-ray diffraction before and after loading. We validated constitutive models using both atomistic molecular dynamics and continuum simulations performed at the boundary of their current computational possibilities to match experimental scales.

Authors:
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
902248
Report Number(s):
UCRL-TR-228484
TRN: US200717%%502
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPRESSION; DEFORMATION; GRAIN SIZE; PLASTICS; STRAIN RATE; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Bringa, E. Final Report LDRD 04-ERD-021. United States: N. p., 2007. Web. doi:10.2172/902248.
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Bringa, E. Final Report LDRD 04-ERD-021. United States. doi:10.2172/902248.
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Bringa, E. Fri . "Final Report LDRD 04-ERD-021". United States. doi:10.2172/902248. https://www.osti.gov/servlets/purl/902248.
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@article{osti_902248,
title = {Final Report LDRD 04-ERD-021},
author = {Bringa, E},
abstractNote = {In this project, we performed experiments and simulations to establish constitutive models for plastic behavior and to determine the deformation mechanism of nanocrystalline materials at different grain sizes (<100 nm) and high strain rates (>10{sup 6}/s). The experiments used both laser-induced shocks and isentropic compression to investigate, for the first time, the high-strain-rate deformation of nanocrystalline Ni. Samples were characterized using transmission electron microscopy, nanoindentation, profilometry, and x-ray diffraction before and after loading. We validated constitutive models using both atomistic molecular dynamics and continuum simulations performed at the boundary of their current computational possibilities to match experimental scales.},
doi = {10.2172/902248},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Feb 23 00:00:00 EST 2007},
month = {Fri Feb 23 00:00:00 EST 2007}
}
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DOI:  10.2172/902248
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