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Title: White beam microdiffraction experiments for the determination ofthe local plastic behaviour of polycrystals

Abstract

The overall plastic behavior of polycrystalline materialsstrongly depends on the microstructure and on the local rheology ofindividual grains. The characterization of the strain and stressheterogeneities within the specimen, which result from the intergranularmechanical interactions, is of particular interest since they largelycontrol the microstructure evolutions such as texture development,work-hardening, damage, recrystallization, etc. The influence ofmicrostructure on the effective behavior can be addressed byphysical-based predictive models (homogenization schemes) based either onfull-field or on mean-field approaches. But these models require theknowledge of the grain behavior, which in turn must be determined on thereal specimen under investigation. The microextensometry technique thathas been developed at the LMS-X allows the determination of the surfacetotal (i.e., plastic + elastic) strain field with a micrometric spatialresolution. On the other hand, the white beam X-ray microdiffractiontechnique developed recently at the Advanced Light Source enables thedetermination of the elastic strain with the same spatial resolution. Forpolycrystalline materials with grain size of about 10 micrometers, acomplete intragranular mechanical characterization can thus be performedby coupling these two techniques. The very first results obtained onplasticallydeformed copper and zirconium specimens arepresented.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US); Advanced Light Source(ALS)
Sponsoring Org.:
USDOE Director. Office of Science. Basic EnergySciences
OSTI Identifier:
926301
Report Number(s):
LBNL-62843
Journal ID: ISSN 0255-5476; MSFOEP; R&D Project: A580ES; BnR: KC0204016; TRN: US0802535
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Science Forum; Journal Volume: 524-525; Related Information: Journal Publication Date: 2006
Country of Publication:
United States
Language:
English
Subject:
36; ADVANCED LIGHT SOURCE; COPPER; GRAIN SIZE; MICROSTRUCTURE; PLASTICS; POLYCRYSTALS; RECRYSTALLIZATION; RHEOLOGY; SPATIAL RESOLUTION; STRAIN HARDENING; STRAINS; TEXTURE; ZIRCONIUM; microdiffraction polycrystal plasticity micromechanics residualstresses

Citation Formats

Castelnau, O., Goudeau, P., Geandier, G., Tamura, N., Bechade,J.L., Bornert, M., and Caldemaison, D. White beam microdiffraction experiments for the determination ofthe local plastic behaviour of polycrystals. United States: N. p., 2006. Web.
Castelnau, O., Goudeau, P., Geandier, G., Tamura, N., Bechade,J.L., Bornert, M., & Caldemaison, D. White beam microdiffraction experiments for the determination ofthe local plastic behaviour of polycrystals. United States.
Castelnau, O., Goudeau, P., Geandier, G., Tamura, N., Bechade,J.L., Bornert, M., and Caldemaison, D. Sun . "White beam microdiffraction experiments for the determination ofthe local plastic behaviour of polycrystals". United States. doi:.
@article{osti_926301,
title = {White beam microdiffraction experiments for the determination ofthe local plastic behaviour of polycrystals},
author = {Castelnau, O. and Goudeau, P. and Geandier, G. and Tamura, N. and Bechade,J.L. and Bornert, M. and Caldemaison, D.},
abstractNote = {The overall plastic behavior of polycrystalline materialsstrongly depends on the microstructure and on the local rheology ofindividual grains. The characterization of the strain and stressheterogeneities within the specimen, which result from the intergranularmechanical interactions, is of particular interest since they largelycontrol the microstructure evolutions such as texture development,work-hardening, damage, recrystallization, etc. The influence ofmicrostructure on the effective behavior can be addressed byphysical-based predictive models (homogenization schemes) based either onfull-field or on mean-field approaches. But these models require theknowledge of the grain behavior, which in turn must be determined on thereal specimen under investigation. The microextensometry technique thathas been developed at the LMS-X allows the determination of the surfacetotal (i.e., plastic + elastic) strain field with a micrometric spatialresolution. On the other hand, the white beam X-ray microdiffractiontechnique developed recently at the Advanced Light Source enables thedetermination of the elastic strain with the same spatial resolution. Forpolycrystalline materials with grain size of about 10 micrometers, acomplete intragranular mechanical characterization can thus be performedby coupling these two techniques. The very first results obtained onplasticallydeformed copper and zirconium specimens arepresented.},
doi = {},
journal = {Materials Science Forum},
number = ,
volume = 524-525,
place = {United States},
year = {Sun Dec 31 00:00:00 EST 2006},
month = {Sun Dec 31 00:00:00 EST 2006}
}
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