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Title: Development of Powder Diffraction Analysis Tools for aNanocrystalline Specimen: An Emphasis upon NiTi (Nitinol)

Abstract

Powder diffraction is a specialized technique whose investigatory limits are constrained by the scale of the crystallized substance being scanned versus the probe beam used. When disparate in scale, with the photon spot size larger than the crystal being probed, many are employed, the resulting diffraction image being cast from all possible incident angles, constructing {chi}-arcs containing information about the crystalline structure of the material under examination. Of particular interest to our collaboration is the structure of Nitinol, a superelastic Nickel-Titanium alloy, whose phase transformations and load bearing deformations can be studied by usage of diffraction, with wide sweeping biomedical uses. Analysis of this data is complicated by phase transformation and material fluorescence, which make difficult the computational modeling of the peaks within concentric {chi}-arcs. We endeavored to construct a series of computational tools (the amalgamation of them known as 2DPeakFinder) for refining and extracting this relevant data, toward the end of employing previously developed algorithms in the material's structural analysis. We succeeded to a large degree with the use of an iterative algorithm to navigate radial complexity of the signal and manage to retain a distinction between useful signal and superfluous background noise. The tools developed in this projectmore » are a small step in readily streamlining the analysis and physical modeling of a Nanocrystalline material's structural properties.« less

Authors:
;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
891239
Report Number(s):
SLAC-TN-06-023
TRN: US200621%%697
DOE Contract Number:
AC02-76SF00515
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALGORITHMS; BACKGROUND NOISE; BEARINGS; DIFFRACTION; FLUORESCENCE; NICKEL ALLOYS; PHASE TRANSFORMATIONS; PHOTONS; PROBES; REFINING; SIMULATION; TITANIUM ALLOYS; Other,OTHER

Citation Formats

Owens, Erich, and /Albion Coll. /SLAC. Development of Powder Diffraction Analysis Tools for aNanocrystalline Specimen: An Emphasis upon NiTi (Nitinol). United States: N. p., 2006. Web. doi:10.2172/891239.
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Owens, Erich, & /Albion Coll. /SLAC. Development of Powder Diffraction Analysis Tools for aNanocrystalline Specimen: An Emphasis upon NiTi (Nitinol). United States. doi:10.2172/891239.
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Owens, Erich, and /Albion Coll. /SLAC. Wed . "Development of Powder Diffraction Analysis Tools for aNanocrystalline Specimen: An Emphasis upon NiTi (Nitinol)". United States. doi:10.2172/891239. https://www.osti.gov/servlets/purl/891239.
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@article{osti_891239,
title = {Development of Powder Diffraction Analysis Tools for aNanocrystalline Specimen: An Emphasis upon NiTi (Nitinol)},
author = {Owens, Erich and /Albion Coll. /SLAC},
abstractNote = {Powder diffraction is a specialized technique whose investigatory limits are constrained by the scale of the crystallized substance being scanned versus the probe beam used. When disparate in scale, with the photon spot size larger than the crystal being probed, many are employed, the resulting diffraction image being cast from all possible incident angles, constructing {chi}-arcs containing information about the crystalline structure of the material under examination. Of particular interest to our collaboration is the structure of Nitinol, a superelastic Nickel-Titanium alloy, whose phase transformations and load bearing deformations can be studied by usage of diffraction, with wide sweeping biomedical uses. Analysis of this data is complicated by phase transformation and material fluorescence, which make difficult the computational modeling of the peaks within concentric {chi}-arcs. We endeavored to construct a series of computational tools (the amalgamation of them known as 2DPeakFinder) for refining and extracting this relevant data, toward the end of employing previously developed algorithms in the material's structural analysis. We succeeded to a large degree with the use of an iterative algorithm to navigate radial complexity of the signal and manage to retain a distinction between useful signal and superfluous background noise. The tools developed in this project are a small step in readily streamlining the analysis and physical modeling of a Nanocrystalline material's structural properties.},
doi = {10.2172/891239},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Aug 30 00:00:00 EDT 2006},
month = {Wed Aug 30 00:00:00 EDT 2006}
}
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DOI:  10.2172/891239
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