Structural and phase evolution in mechanically alloyed calcium copper titanate dielectrics
Author
Alizadeh, M.
Ardakani H.A.
Amini, R.
Ghazanfari, M.R.
Ghaffari, M.
Date
2013Source Title
Ceramics International
Print ISSN
0272-8842
Volume
39
Issue
3
Pages
3307 - 3312
Language
English
Type
ArticleItem Usage Stats
127
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Abstract
Nanocrystalline calcium-copper-titanate (CCTO) dielectric powders were prepared by mechanical alloying. Phase transformations and structural evolution of the mechanically activated powders were investigated through the Rietveld refinement of the X-ray diffraction results. The crystallite size, lattice strain, and weight fraction of individual phases were estimated based on crystal structure refinement. Furthermore, the microstructural properties and thermal behavior of the milled powders were investigated by Transmission Electron Microscopy (TEM) and Differential Thermal Analysis (DTA), respectively. It was found that CCTO nanocrystals can be successfully synthesized after the amorphization of the initial crystalline materials. Semi-spherical nano-size particles were developed after sufficient milling time. Formation of an amorphous phase during the milling cycle was confirmed by the presence of the glass transition and crystallization peaks in the thermal analysis profiles. © 2012 Elsevier Ltd and Techna Group S.r.l.
Keywords
Amorphous phaseC. Thermal properties
Dielectrics
Mechanical alloying
Amorphous phase
Calcium copper titanates
Crystal structure refinement
Dielectric powders
Lattice strain
Mechanically alloyed
Microstructural properties
Milled powders
Milling cycles
Milling time
Nano-size particles
Nanocrystallines
Phase evolutions
Structural evolution
Thermal behaviors
Transmission electron microscopy tem
Weight fractions
Crystal structure
Crystalline materials
Differential thermal analysis
Glass transition
Mechanical alloying
Milling (machining)
Nanocrystalline powders
Powders
Rietveld refinement
Transmission electron microscopy
X ray diffraction
X ray powder diffraction
Dielectric materials
Permalink
http://hdl.handle.net/11693/21024Published Version (Please cite this version)
http://dx.doi.org/10.1016/j.ceramint.2012.10.019Collections
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