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Title: Scaling, Microstructure and Dynamic Fracture

Abstract

The relationship between pullback velocity and impact velocity is studied for different microstructures in Cu. A size distribution of potential nucleation sites is derived under the conditions of an applied stochastic stress field. The size distribution depends on flow stress leading to a connection between the plastic flow appropriate to a given microstructure and nucleation rate. The pullback velocity in turn depends on the nucleation rate resulting in a prediction for the relationship between pullback velocity and flow stress. The theory is compared to observations of Cu on Cu gas-gun experiments (10-50 GPa) for a diverse set of microstructures. The scaling law is incorporated into a 1D finite difference code and is shown to reproduce the experimental data with one adjustable parameter that depends only on a nucleation exponent, {Lambda}.

Authors:
; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
928174
Report Number(s):
UCRL-CONF-217905
TRN: US0804299
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: Presented at: Scaling, Microstructure and Dynamic failure, Baltimore, MD, United States, Oct 02 - Oct 05, 2005
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DISTRIBUTION; FLOW STRESS; FORECASTING; FRACTURES; MICROSTRUCTURE; NUCLEATION; PLASTICS; SCALING LAWS; VELOCITY

Citation Formats

Minich, R W, Kumar, M, Schwarz, A, and Cazamias, J. Scaling, Microstructure and Dynamic Fracture. United States: N. p., 2005. Web.
Minich, R W, Kumar, M, Schwarz, A, & Cazamias, J. Scaling, Microstructure and Dynamic Fracture. United States.
Minich, R W, Kumar, M, Schwarz, A, and Cazamias, J. Wed . "Scaling, Microstructure and Dynamic Fracture". United States. doi:. https://www.osti.gov/servlets/purl/928174.
@article{osti_928174,
title = {Scaling, Microstructure and Dynamic Fracture},
author = {Minich, R W and Kumar, M and Schwarz, A and Cazamias, J},
abstractNote = {The relationship between pullback velocity and impact velocity is studied for different microstructures in Cu. A size distribution of potential nucleation sites is derived under the conditions of an applied stochastic stress field. The size distribution depends on flow stress leading to a connection between the plastic flow appropriate to a given microstructure and nucleation rate. The pullback velocity in turn depends on the nucleation rate resulting in a prediction for the relationship between pullback velocity and flow stress. The theory is compared to observations of Cu on Cu gas-gun experiments (10-50 GPa) for a diverse set of microstructures. The scaling law is incorporated into a 1D finite difference code and is shown to reproduce the experimental data with one adjustable parameter that depends only on a nucleation exponent, {Lambda}.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Dec 21 00:00:00 EST 2005},
month = {Wed Dec 21 00:00:00 EST 2005}
}

Conference:
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