Void Morphology In NiAl

2000 ◽  
Vol 646 ◽  
Author(s):  
M. Zakaria ◽  
P.R. Munroe
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Surface Energy ◽  
Annealing Temperature ◽  
Void Formation ◽  
Dislocation Climb ◽  
Annealing Temperatures ◽  
Relative Incidence ◽  
Transmission Electron ◽  
Void Shape

ABSTRACTVoid formation in stoichiometric NiAl was studied through controlled heat treatments and transmission electron microscopy. Voids formed at temperatures as low as 400°C, but dissolved during annealing at 900°C. Both cuboidal and rhombic dodecahedral voids were observed, often at the same annealing temperature. At higher annealing temperatures (>800°C) extensive dislocation climb was noted. The relative incidence of void formation and dislocation climb can be related to the mobility of vacancies at each annealing temperature. Further, differences in void shape can be described in terms of their relative surface energy and mode of nucleation.

CoSi2 Precipitate Coarsening During Formation of Buried Epitaxial Cosi2 Layers By Ion Beam Synthesis

1990 ◽  
Vol 201 ◽  
Author(s):  
R. Jebasinski ◽  
S. Mantl ◽  
K. Radermacher ◽  
P. Fichtner ◽  
W. Jăger ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Activation Energy ◽  
Transmission Electron Microscopy ◽  
Cross Section ◽  
Microstructural Evolution ◽  
Annealing Temperature ◽  
Ion Beam ◽  
Precipitate Coarsening ◽  
Annealing Temperatures ◽  
Transmission Electron

AbstractThe coarsening of CoSi2 precipitates and the microstructural evolution of (111) Si implanted with 200 keV Co+ ions at 350°C and fluences of 1×1016cm−2 and 6×1016cm−2 were investigated as a function of depth, annealing temperature and annealing time using Rutherford Backscattering Spectroscopy (RBS) and Transmission Electron Microscopy (TEM). After annealing cross-section TEM micrographs show a layered array of platelet-shaped precipitates with preferred facets on {111} planes. The fraction of Co-atoms, that were redistributed during the different annealing temperatures and times, has been used to determine an activation energy for the precipitate coarsening. By applying the Meechan-Brinkman and the change-of-slope methods, we obtained activation energies in the range of 3.2 – 3.6 eV.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

Diffusion Process Of Interstitial Atoms In Inp Studied By Transmission Electron Microscopy

1996 ◽  
Vol 442 ◽  
Author(s):  
Y. Ohno ◽  
S. Takeda ◽  
M. Hirata
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Diffusion Process ◽  
Annealing Temperature ◽  
Number Density ◽  
Electron Dose ◽  
Final Density ◽  
Maximum Value ◽  
Transmission Electron ◽  
Interstitial Atoms

AbstractIt is found that interstitial agglomerates are formed uniformly in an irradiated area of InP by annealing at the temperature above 700 K after 200 keV-electron irradiation. TEM observation shows that the number density of interstitial atoms in the agglomerates reached a maximum value when the growth of all the agglomerates stopped. The final density did not depend on annealing temperature but on electron dose, and it increased quadratically with electron dose up to 2×1022 cm−2. In order to explain the experimental results, we have proposed a new model that the agglomerates are formed by thermal diffusion and agglomeration of interstitial-pairs, i.e. Ini-Pi interstitial-pairs. From the analysis, the migration energies for the pairs are estimated to be 1.52 eV. The onset temperature for the diffusion of the pairs is estimated as 550 K.

scholarly journals Влияние термообработки на свойства композитных кремний-углеродных анодов для литий-ионных аккумуляторов

2020 ◽  
Vol 46 (3) ◽  
pp. 14
Author(s):  
Е.В. Астрова ◽  
А.В. Парфеньева ◽  
А.М. Румянцев ◽  
В.П. Улин ◽  
М.В. Байдакова ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Silicon Carbide ◽  
Diffraction Analysis ◽  
Annealing Temperature ◽  
Argon Atmosphere ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Lithium Alloys

The effect of annealing temperature in argon atmosphere on the ability of Si-C nanocomposites to reversibly insert lithium was investigated. It was found that the higher the annealing temperature during the formation of the composite, the lower is the capacitance of the electrode made from it. X-ray diffraction analysis and transmission electron microscopy reveal that the reason of the capacitance decrease is formation at T  1100°C of silicon carbide of cubic modification -SiC, inactive with respect to the formation of lithium alloys or intercalates.

scholarly journals Structural Changes in Nickel Silicide Thin Films under the Presence of Al and Ga

2010 ◽  
Vol 638-642 ◽  
pp. 2938-2943 ◽  
Author(s):  
A.V. Mogilatenko ◽  
Frank Allenstein ◽  
M.A. Schubert ◽  
Meiken Falke ◽  
G. Beddies ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Room Temperature ◽  
Structural Changes ◽  
Annealing Temperature ◽  
Nickel Silicide ◽  
Subsequent Annealing ◽  
Formation Temperature ◽  
Transmission Electron

Thin Ni/Al and Ni/Ga layers of different atomic ratios were codeposited onto Si(001) at room temperature followed by subsequent annealing. Influence of annealing temperature on morphology and composition of ternary disilicide NiSi2-xAlx and NiSi2-xGax layers was investigated by transmission electron microscopy. Addition of Al or Ga leads to a decrease of the disilicide formation temperature from 700°C down to at least 500°C. Depending on the composition closed, uniformly oriented NiSi2-xAlx and NiSi2-xGax layers were observed after annealing at 900°C, whereas reaction of a pure Ni film with Si leads to the island formation with a mixture of A- and B-type orientations.

Microstructures of Amorphic Diamond™ Films Deposited by Laser-Ablation

1995 ◽  
Vol 416 ◽  
Author(s):  
Hyunchul Sohn ◽  
Kannan Krishnan ◽  
Richard Fink
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Laser Ablation ◽  
Energy Loss ◽  
Annealing Temperature ◽  
Laser Ablation Method ◽  
Transmission Electron ◽  
Large Particles ◽  
Particulate Size ◽  
Electron Energy Loss

ABSTRACTMicrostructures of Amorphic Diamond™ films deposited by laser ablation method were investigated using transmission electron microscopy. The AD films matrix was homogeneous with a sp3-type bonding fraction of 40%∼45% confirmed by electron energy-loss spectroscopy. The sp3 bonding fraction decreased monotonically with increasing annealing temperature. The main inhomogeneity in Amorphic Diamond™ was observed to be particulates of high density (>105/cm2) distributed through the depth of the film. Particulate size ranged from ∼10nm to a few μm and most of them were identified to be graphite. Large particles (>0.5μm) were agglomerates of smaller graphite crystallites. Possible mechanisms for cold field emission are discussed based on the microstructures observed in these AD films.

Investigation of Intermetallic Phase Formation and Structural Analysis in Annealed Al/Cu Bilayer Thin Films

2013 ◽  
Vol 845 ◽  
pp. 221-225
Author(s):  
Zulhelmi Alif Abdul Halim ◽  
Muhammad Azizi Mat Yajid ◽  
Zulkifli Mohd Rosli ◽  
Riyaz Ahmad Mohamad Ali
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Structural Analysis ◽  
Annealing Temperature ◽  
Intermetallic Phase ◽  
Intermetallic Phases ◽  
X Ray ◽  
Transmission Electron

The growth of intermetallic phases in Al/Cu bilayers thin film having 2/3 layer thickness ratios were characterized by X-ray powder diffraction (XRD), energy dispersive X-ray (EDX) and transmission electron microscopy (TEM). In annealing temperature of 200 °C, the growth is controlled by Cu diffusion which resulted to formation of θ-Al2Cu, η-AlCu, ζ-Al3Cu4 and γ-Al4Cu9 phase.

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