Effect of numerical parameters on characterizing the hardening behavior of ductile uniaxial tension specimens.
Abstract
Many problems of practical importance involve ductile materials that undergo very large strains, in many cases to the point of failure. Examples include structures subjected to impact or blast loads, energy absorbing devices subjected to significant crushing, coldforming manufacturing processes and others. One of the most fundamental pieces of data that is required in the analysis of this kind of problems is the fit of the uniaxial stressstrain curve of the material. A series of experiments where mild steel plates were punctured with a conical indenter provided a motivation to characterize the true stressstrain curve until the point of failure of this material, which displayed significant ductility. The hardening curve was obtained using a finite element model of the tensile specimens that included a geometric imperfection in the form of a small reduction in the specimen width to initiate necking. An automated procedure iteratively adjusted the true stressstrain curve fit used as input until the predicted engineering stressstrain curve matched experimental measurements. Whereas the fitting is relatively trivial prior to reaching the ultimate engineering stress, the fit of the softening part of the engineering stressstain curve is highly dependent on the finite element parameters such as element formulation and initialmore »
 Authors:
 Publication Date:
 Research Org.:
 Sandia National Laboratories
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1030391
 Report Number(s):
 SAND20107897C
TRN: US201124%%176
 DOE Contract Number:
 AC0494AL85000
 Resource Type:
 Conference
 Resource Relation:
 Conference: Proposed for presentation at the American Society of Mechanical Engineers Internation Mechanical Engineering Congress and Exposition held November 1518, 2010 in Vancouver, BC, Canada.
 Country of Publication:
 United States
 Language:
 English
 Subject:
 36 MATERIALS SCIENCE; ASPECT RATIO; CRUSHING; DEFECTS; DUCTILITY; ENGINEERS; GEOMETRY; HARDENING; MANUFACTURING; REFINING; STEELS; STRAINS
Citation Formats
Cordova, Theresa Elena, Dion, Kristin, Laing, John Robert, Corona, Edmundo, Breivik, Nicole L., Wellman, Gerald William, and Shelton, Timothy R. Effect of numerical parameters on characterizing the hardening behavior of ductile uniaxial tension specimens.. United States: N. p., 2010.
Web.
Cordova, Theresa Elena, Dion, Kristin, Laing, John Robert, Corona, Edmundo, Breivik, Nicole L., Wellman, Gerald William, & Shelton, Timothy R. Effect of numerical parameters on characterizing the hardening behavior of ductile uniaxial tension specimens.. United States.
Cordova, Theresa Elena, Dion, Kristin, Laing, John Robert, Corona, Edmundo, Breivik, Nicole L., Wellman, Gerald William, and Shelton, Timothy R. 2010.
"Effect of numerical parameters on characterizing the hardening behavior of ductile uniaxial tension specimens.". United States.
doi:.
@article{osti_1030391,
title = {Effect of numerical parameters on characterizing the hardening behavior of ductile uniaxial tension specimens.},
author = {Cordova, Theresa Elena and Dion, Kristin and Laing, John Robert and Corona, Edmundo and Breivik, Nicole L. and Wellman, Gerald William and Shelton, Timothy R.},
abstractNote = {Many problems of practical importance involve ductile materials that undergo very large strains, in many cases to the point of failure. Examples include structures subjected to impact or blast loads, energy absorbing devices subjected to significant crushing, coldforming manufacturing processes and others. One of the most fundamental pieces of data that is required in the analysis of this kind of problems is the fit of the uniaxial stressstrain curve of the material. A series of experiments where mild steel plates were punctured with a conical indenter provided a motivation to characterize the true stressstrain curve until the point of failure of this material, which displayed significant ductility. The hardening curve was obtained using a finite element model of the tensile specimens that included a geometric imperfection in the form of a small reduction in the specimen width to initiate necking. An automated procedure iteratively adjusted the true stressstrain curve fit used as input until the predicted engineering stressstrain curve matched experimental measurements. Whereas the fitting is relatively trivial prior to reaching the ultimate engineering stress, the fit of the softening part of the engineering stressstain curve is highly dependent on the finite element parameters such as element formulation and initial geometry. Results by two hexahedral elements are compared. The first is a standard, underintegrated, uniformstrain element with hourglass control. The second is a modified selectivelyreducedintegration element. In addition, the effects of element size, aspect ratio and hourglass control characteristics are investigated. The effect of adaptively refining the mesh based on the aspect ratio of the deformed elements is also considered. The results of the study indicate that for the plate puncture problem, characterizing the material with the same element formulation and size as used in the plate models is beneficial. On the other hand, using different element formulations, sizes or initial aspect ratios can lead to unreliable results.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2010,
month =
}

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