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Title: An In-situ method for the study of strain broadening usingsynchrotronx-ray diffraction

Abstract

A tensonometer for stretching metal foils has beenconstructed for the study of strain broadening in x-ray diffraction lineprofiles. This device, which is designed for use on the powderdiffractometer in Station 2.3 at Daresbury Laboratory, allows in-situmeasurements to be performed on samples under stress. It can be used fordata collection in either transmission or reflection modes using eithersymmetric or asymmetric diffraction geometries. As a test case,measurements were carried out on a 18mum thick copper foil experiencingstrain levels of up to 5 percent using both symmetric reflection andsymmetric transmission diffraction. All the diffraction profilesdisplayed peak broadening and asymmetry which increased with strain. Themeasured profiles were analysed by the fundamental parameters approachusing the TOPAS peak fitting software. All the observed broadenedprofiles were modelled by convoluting a refineable diffraction profile,representing the dislocation and crystallite size broadening, with afixed instrumental profile pre-determined usinghigh quality LaB6reference powder. The de-convolution process yielded "pure" sampleintegral breadths and asymmetry results which displayed a strongdependence on applied strain and increased almost linearly with appliedstrain. Assuming crystallite size broadening in combination withdislocation broadening arising from fcc a/2<110>111 dislocations,we have extracted the variation of mechanic al property with strain. Theobservation of both peak asymmetry and broadening has been interpreted asa manifestation ofmore » a cellular structure with cell walls and cellinteriors possessing high and low dislocation densities.« less

Authors:
; ; ;
Publication Date:
Research Org.:
COLLABORATION - Diamond LightSource/UK
Sponsoring Org.:
USDOE Director. Office of Science. Basic EnergySciences
OSTI Identifier:
928773
Report Number(s):
LBNL-62127
Journal ID: ISSN 0021-8898; JACGAR; R&D Project: A580ES; BnR: KC0204016; TRN: US0803258
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Crystallography; Journal Volume: 40; Journal Issue: 4; Related Information: Journal Publication Date: 01/2007
Country of Publication:
United States
Language:
English
Subject:
47; 36; ASYMMETRY; CELL WALL; COPPER; DIFFRACTION; DIFFRACTOMETERS; DISLOCATIONS; REFLECTION; STRAINS; SYNCHROTRONS; X-RAY DIFFRACTION; Line Broadening Analysis Crystallite Size Determination In-situStrain analysis Synchrotron X-ray Diffraction

Citation Formats

Tang, Chiu C., Lynch, Peter A., Cheary, Robert W., and Clark, Simon M. An In-situ method for the study of strain broadening usingsynchrotronx-ray diffraction. United States: N. p., 2006. Web.
Tang, Chiu C., Lynch, Peter A., Cheary, Robert W., & Clark, Simon M. An In-situ method for the study of strain broadening usingsynchrotronx-ray diffraction. United States.
Tang, Chiu C., Lynch, Peter A., Cheary, Robert W., and Clark, Simon M. Fri . "An In-situ method for the study of strain broadening usingsynchrotronx-ray diffraction". United States. doi:. https://www.osti.gov/servlets/purl/928773.
@article{osti_928773,
title = {An In-situ method for the study of strain broadening usingsynchrotronx-ray diffraction},
author = {Tang, Chiu C. and Lynch, Peter A. and Cheary, Robert W. and Clark, Simon M.},
abstractNote = {A tensonometer for stretching metal foils has beenconstructed for the study of strain broadening in x-ray diffraction lineprofiles. This device, which is designed for use on the powderdiffractometer in Station 2.3 at Daresbury Laboratory, allows in-situmeasurements to be performed on samples under stress. It can be used fordata collection in either transmission or reflection modes using eithersymmetric or asymmetric diffraction geometries. As a test case,measurements were carried out on a 18mum thick copper foil experiencingstrain levels of up to 5 percent using both symmetric reflection andsymmetric transmission diffraction. All the diffraction profilesdisplayed peak broadening and asymmetry which increased with strain. Themeasured profiles were analysed by the fundamental parameters approachusing the TOPAS peak fitting software. All the observed broadenedprofiles were modelled by convoluting a refineable diffraction profile,representing the dislocation and crystallite size broadening, with afixed instrumental profile pre-determined usinghigh quality LaB6reference powder. The de-convolution process yielded "pure" sampleintegral breadths and asymmetry results which displayed a strongdependence on applied strain and increased almost linearly with appliedstrain. Assuming crystallite size broadening in combination withdislocation broadening arising from fcc a/2<110>111 dislocations,we have extracted the variation of mechanic al property with strain. Theobservation of both peak asymmetry and broadening has been interpreted asa manifestation of a cellular structure with cell walls and cellinteriors possessing high and low dislocation densities.},
doi = {},
journal = {Journal of Applied Crystallography},
number = 4,
volume = 40,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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