ChemInform Abstract: Electric Conductivity in Electrofused Magnesia with Non-Equilibrium Defects.

ChemInform ◽  
2010 ◽  
Vol 24 (34) ◽  
pp. no-no
Author(s):  
M. KOBUNE ◽  
Y. SUGIE ◽  
S. FUJII
2008 ◽  
Vol 277 ◽  
pp. 69-74
Author(s):  
Andriy O. Koval'chuk ◽  
D.S. Gertsriken ◽  
Andriy Gusak ◽  
V.F. Mazanko

Since 1975 a so-called anomalous mass-transfer in metals and alloys under pulse loading is being investigated in the Institute of Metal Physics. This phenomenon remains to be a challenge to theoreticians. Besides, one more phenomenon (observed at the same systems) was discovered – formation of metastable alloys (solutions, and, sometimes, ordered phases), with solubility limits far exceeding the equilibrium values and depending on the deformation rate. Since formation of nonequilibrium phases is also typical for alloys under irradiation, it seemed natural for us to use some of concepts and models invented in the “materials under irradiation” community. We propose 3 types of models for description of metastable solid solution formation in diffusion couple under pulse loading: 1) flux balance for both components at the interface with account of non-equilibrium defects generated during pulse loading; 2) “ballistic jump” concept, which had been invented by George Martin et al. for materials under irradiation or ball-milling, combined with another Martin’s kinetic model (1994) of diffusion; 3) modification of such a concept for the case of non-equilibrium interstitial defects. Non-equilibrium phase diagrams obtained by all 3 models are built and compared with experimental data which reflect a qualitative correspondence to one another.


2005 ◽  
Vol 20 (10) ◽  
pp. 2866-2872 ◽  
Author(s):  
Haruki Ryoken ◽  
Isao Sakaguchi ◽  
Naoki Ohashi ◽  
Takashi Sekiguchi ◽  
Shunichi Hishita ◽  
...  

Zinc oxide (ZnO) films doped with aluminum (Al) were deposited with a pulsed laser deposition technique to characterize the charge compensation phenomena in ZnO. In particular, oxygen radical (O*) irradiation during film deposition was used to modify the oxygen stoichiometry. Irradiation with O* decreased electron concentration in Al-doped ZnO. The lattice parameter of the resultant films also varied with the growth conditions. However, no obvious correlation between electron concentration and lattice parameter was found. The self-diffusion coefficients indicated the presence of non-equilibrium defects. The properties of the films are discussed from the viewpoint of non-equilibrium compensated defects detected in the diffusion measurements.


1987 ◽  
Author(s):  
Z. E. Smith ◽  
S. Aljishi ◽  
D. -S. Shen ◽  
V. Chu ◽  
D. Slobodin ◽  
...  

1980 ◽  
Vol 35 (10) ◽  
pp. 759-763 ◽  
Author(s):  
C.W. Schulte ◽  
J.L. Campbell ◽  
K.W.D. Ledingham ◽  
P.C. Lichtenberger

Author(s):  
Edward A Kenik

Segregation of solute atoms to grain boundaries, dislocations, and other extended defects can occur under thermal equilibrium or non-equilibrium conditions, such as quenching, irradiation, or precipitation. Generally, equilibrium segregation is narrow (near monolayer coverage at planar defects), whereas non-equilibrium segregation exhibits profiles of larger spatial extent, associated with diffusion of point defects or solute atoms. Analytical electron microscopy provides tools both to measure the segregation and to characterize the defect at which the segregation occurs. This is especially true of instruments that can achieve fine (<2 nm width), high current probes and as such, provide high spatial resolution analysis and characterization capability. Analysis was performed in a Philips EM400T/FEG operated in the scanning transmission mode with a probe diameter of <2 nm (FWTM). The instrument is equipped with EDAX 9100/70 energy dispersive X-ray spectrometry (EDXS) and Gatan 666 parallel detection electron energy loss spectrometry (PEELS) systems. A double-tilt, liquid-nitrogen-cooled specimen holder was employed for microanalysis in order to minimize contamination under the focussed spot.


Author(s):  
Michel Le Bellac ◽  
Fabrice Mortessagne ◽  
G. George Batrouni

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