scholarly journals Coordination Spheres Effect On RecompositionAtoms In AB Alloys

2017 ◽  
Vol 27 (4) ◽  
Author(s):  
Abdulhalim Kh. Ali ◽  
A. A. AL-Rubaiee ◽  
Marwah M. Abdulsttar
Keyword(s):  
Computer Simulation ◽  
Long Range ◽  
Interatomic Interaction ◽  
Antiphase Domain ◽  
Range Order ◽  
Long Range Order ◽  
Defect Clusters ◽  
Coordination Spheres ◽  
Two Phases ◽  
Point Defect Clusters

This study focused on the variation of the long-range order parameters with temperature for nine coordination spheres. The computer simulation results showed several mechanismsof atoms disordering. These mechanisms are represented in: (Substitution point defect, Clusters and Segregations, Micro domain, Antiphase order and Antiphase boundaries.  As the number of coordination spheres increase, the interatomic interaction increase with a decrease in the ordered phase stability. In the initial stages of the computer simulation two phases in the alloy is found, an ordered phase of   long-range order and ordered phase of   antiphase domain. In final stages an ordered phase of short –range order is found.  

The Effect of Growth Temperature and Substrate Misorientation on Degree of Order and Antiphase Domain Size in Ga0.52In0.48P Epilayers Grown on GaAs (001) Substrates by Gs-Mbe

1998 ◽  
Vol 523 ◽  
Author(s):  
C. Meenakarn ◽  
A. E. Staton-bevan ◽  
S. P. Najda ◽  
G. Duggan ◽  
A. H. Kean
Keyword(s):  
Band Gap ◽  
Long Range ◽  
Growth Temperature ◽  
Order Parameter ◽  
Plate Thickness ◽  
Antiphase Domain ◽  
Range Order ◽  
Range Order Parameter ◽  
Long Range Order ◽  
Gaas Substrates

AbstractA Transmission Electron Microscopy (TEM), Photoluminescence (PL) and Photoluminescence Excitation Spectroscopy (PLE) investigation has been conducted on Ga0.52In0.48P epilayers grown on (001) GaAs substrates by Gas-Source Molecular Beam Epitaxy.For Ga0.52In0.48P epilayers grown on exact (001) GaAs substrates, increasing the growth temperature from 480°C to 535°C increased the antiphase domain plate thickness, t, from 7.3±0.4 to 17.4±0.9 Å, and decreased the long range order parameter, n, from 0.32 to 0.18±0.1. For epilayers grown at 530°C, on GaAs(001) substrates off-cut 0°, 7°, 10° and 15° towards [111]A, increasing the substrate misorientation from 0° to 15° decreased the antiphase domain plate thickness, from 12.3±0.6 to 6.0±0.3 Å. The long range order parameter also decreased from 0.19 to 0.10±0.01.The band gap energies of these samples, grown by GS-MBE, were close to those reported for fully disordered Ga0.52In0.48P epilayers grown by MOCVD at ∼760°C. This shows that GSMBE is also a good technique to grow GaInP for high band gap optical data storage applications and at lower growth temperatures. The optimum growth conditions in this study were at a growth temperature of 530°C on (001) GaAs substrate with 15° off-cut towards [111]A.

Computer Simulation of Evolution of Ordering Phases and the Boundaries of Ni-Cr-Al Alloy

2011 ◽  
Vol 233-235 ◽  
pp. 1782-1785
Author(s):  
Zhong Chu ◽  
Guo Qun Zhao
Keyword(s):  
Computer Simulation ◽  
Long Range ◽  
Phase Field ◽  
Field Model ◽  
Phase Field Model ◽  
Range Order ◽  
Precipitation Process ◽  
Al Alloy ◽  
Long Range Order

Based on the microscope phase-field model，the evolution of atom morphology, the long range order(lro) parameter and concentration can be gotten, and atomic clustering and ordering during the precipitation process of Ni-Cr-Al alloy could be obtained. The Ni-14at.%Cr-15.5at.%Al alloy is studied and the temperature of precipitation are 973K. It was showed that the ordering of both Al and Cr atoms take place simultaneously during the precipitation process of Ni-Al-Cr alloy, Cr atoms transfer to the boundaries of L12phases, the domain of rich Cr atoms are formed. At the boundaries of L12phases, Cr atoms may substitute the Al sublattice, and the D022phases are formed.

Computer simulation of long-range order relaxation in homogeneous systems

2002 ◽  
Vol 324 (1-2) ◽  
pp. 11-15 ◽  
Author(s):  
P. Oramus ◽  
R. Kozubski ◽  
V. Pierron-Bohnes ◽  
M.C. Cadeville ◽  
C. Massobrio ◽  
...  
Keyword(s):  
Computer Simulation ◽  
Long Range ◽  
Range Order ◽  
Long Range Order ◽  
Homogeneous Systems

Observation of a Magnetic Antiphase Domain Structure with Long-Range Order in a Synthetic Gd-Y Superlattice

1986 ◽  
Vol 56 (25) ◽  
pp. 2700-2703 ◽  
Author(s):  
C. F. Majkrzak ◽  
J. W. Cable ◽  
J. Kwo ◽  
M. Hong ◽  
D. B. McWhan ◽  
...  
Keyword(s):  
Domain Structure ◽  
Long Range ◽  
Antiphase Domain ◽  
Range Order ◽  
Long Range Order

Observation of a Magnetic Antiphase Domain Structure with Long-Range Order in a Synthetic Gd-Y Superlattice

1986 ◽  
Vol 57 (7) ◽  
pp. 923-923
Author(s):  
C. F. Majkrzak ◽  
J. W. Cable ◽  
J. Kwo ◽  
M. Hong ◽  
D. B. McWhan ◽  
...  
Keyword(s):  
Domain Structure ◽  
Long Range ◽  
Antiphase Domain ◽  
Range Order ◽  
Long Range Order

Chemical Ordering and Microstructural Affects on Magnetic Properties of Sm2Fe17 and Sm2Fe17Nx

1999 ◽  
Vol 577 ◽  
Author(s):  
B.E. Meacham ◽  
K.W. Dennis ◽  
R.W. Mccallum ◽  
J.E. Shield
Keyword(s):  
Long Range ◽  
Domain Walls ◽  
Antiphase Domain ◽  
Small Degree ◽  
Range Order ◽  
Long Range Order ◽  
Chemical Order ◽  
Chemical Ordering ◽  
Random Anisotropy ◽  
Magnetic Hardness

ABSTRACTThe effect of chemical order and defect structure on the magnetization process in Sm2Fe17 and Sm2Fe17Nx has been investigated. In Sm2Fe17, chemical disorder results in the development of random anisotropy and a small degree of magnetic hardness. The anisotropy is reduced as long-range order increases. The motion of domain walls in Sm2Fe17Nx is more dependent on the antiphase domain structure than on the amount of long-range order.

Sign in / Sign up

Export Citation Format

Share Document