Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Initial crystallization in a nanostructured Al-Sm rare earth alloy
Date
2010-06-15
Author
Kalay, Yunus Eren
Chumbley, L. S.
Kramer, M. J.
Anderson, I. E.
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
199
views
0
downloads
Cite This
The transformation kinetics and microstructural evolution during initial crystallization in highly driven Al(90)Sm(10) were investigated using transmission electron microscopy (TEM). conventional Cu K(alpha) and high-energy synchrotron X-ray diffraction (HEXRD) and differential scanning calorimetry (DSC). The highest cooling rate obtained in this study yielded a high number density of fcc-Al nanocrystals, with sizes on the order of 2-5 nm, embedded in a disordered matrix rich in an Al-Sm medium range order (MRO) structure. Isothermal in-situ HEXRD results indicated a single crystallization of a large primitive cubic phase from the disordered state. Further analysis using DSC showed two crystallization events; a small peak overlapping the peak from the main crystallization event. TEM analysis performed at different stages of crystallization resolved pre-existing fcc-Al crystals, further crystallization of fcc-Al, (corresponding to the first small peak) and evolution of the cubic phase, corresponding to the main crystallization event. Fcc-Al nanocrystals showed a restricted growth and stayed at an average size of 16 nm after full crystallization was established. Transformation kinetics was described using Johnson-Mehl-Avrami approach after deconvolution of the overlapping crystallization peaks using a Gaussian approximation.
Subject Keywords
Materials Chemistry
,
Electronic, Optical and Magnetic Materials
,
Condensed Matter Physics
,
Ceramics and Composites
URI
https://hdl.handle.net/11511/36010
Journal
JOURNAL OF NON-CRYSTALLINE SOLIDS
DOI
https://doi.org/10.1016/j.jnoncrysol.2010.05.005
Collections
Department of Metallurgical and Materials Engineering, Article
Suggestions
OpenMETU
Core
Kinetics of fcc-Al nanocrystallization in Al90Tb10 metallic glass
DEMIRTAS, T.; Kalay, Yunus Eren (Elsevier BV, 2013-10-15)
The crystallization kinetics of Al90Tb10 amorphous alloy were investigated by a combined study of differential scanning calorimetry (DSC), transmission electron microscopy (TEM), Cu-K alpha X-ray diffraction (XRD) analyses and microhardness measurements. Amorphous to fcc-Al transformation kinetics were descried through Johnson-Mehl-Avrami OMA) approach based on the isothermal DSC hold at 220 degrees C. XRD and TEM revealed the formation of highly populated (similar to 10(21) m(-3)) fcc-Al nanocrystals after...
Theoretical prediction of bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys
SUER, Sila; Mehrabov, Amdulla; Akdeniz, Mahmut Vedat (Elsevier BV, 2009-03-01)
The bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys has been evaluated via theoretical modeling and computer simulation studies based on a combination of electronic theory of alloys in the pseudopotential approximation and the statistical thermodynamical theory of liquid alloys The. magnitude of atomic ordering energies, calculated by means of the electronic theory of alloys in the pseudopotential approximation, was subsequently used for calculation of the key thermodynamic parameters...
Characterization of Ge nanocrystals embedded in SiO2 by Raman spectroscopy
Serincan, U; Kartopu, G; Guennes, A; Finstad, TG; Turan, Raşit; Ekinci, Y; Bayliss, SC (IOP Publishing, 2004-02-01)
Ge nanocrystals formed in a SiO2 matrix by ion implantation were studied by Raman spectroscopy. It is shown that Raman analysis based on the phonon confinement model yields a successful explanation of the peculiar characteristics resulting from the nanocrystals. A broadening and a shift in the Raman peak are expected to result from the reduced size of the crystals. Asymmetry in the peak is attributed to the variations in the size of the nanocrystals. These effects were observed experimentally for the Ge nan...
Evolution of magnetic and structural properties of TiO2 with Co-doping
Topal, Ugur; Ozkan, Husnu; Bakan, Halil I.; Cankur, Oktay; Topal, Kevser (Elsevier BV, 2008-03-15)
This paper presents the phase formations and magnetic properties of Co-doped TiO2 synthesized by the colloidal and ammonium nitrate melt techniques (ANMT). The phase formations and ferromagnetic properties were studied with XRD and SQUID magnetometry. Crystallization of the TiO2 rutile lattice was completed at 1000 degrees C and that was preserved during annealing up to 1300 degrees C. For the samples annealed at 1200 degrees C, elemental analysis has shown that the colloidal technique leads to a single-pha...
Stability analysis of graphene nanoribbons by molecular dynamics simulations
Dugan, N.; Erkoç, Şakir (Wiley, 2008-04-01)
In this work, stability of graphene nanoribbons are investigated using molecular dynamics. Simulations include heating armchair and zigzag-edged nanoribbons of widths varying between one and nine hexagonal rings until the bonds between carbon atoms start to break. Breaking temperatures and binding energies per atom for different widths are presented for both armchair and zigzag-edged cases. A nontrivial relation between stability and width is observed and discussed.
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
Y. E. Kalay, L. S. Chumbley, M. J. Kramer, and I. E. Anderson, “Initial crystallization in a nanostructured Al-Sm rare earth alloy,”
JOURNAL OF NON-CRYSTALLINE SOLIDS
, pp. 1416–1424, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36010.