COMPUTATIONAL MODELING OF MATERIALS: THREE HIERARCHICAL LEVELS

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COMPUTATIONAL MODELING OF MATERIALS THREE
HIERARCHICAL LEVELS
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Embedded Atom Method Energy Functions (D.J.Oh and
R.A.Johnson, 1989 ,Atomic Simulation of
Materials, EdtsV Vitek and D.J.Srolovitz,p 233)

The total internal energy of the crystal
where
and
Internal energy associated with atom i Embedded
Energy of atom i. Contribution to electron
density of ith atom and jth atom.   Two
body central potential between ith atom and jth
atom.  
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Embedded energy is of the form
where
are equilibrium and cut off interatomic
separations
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The constants required in the above equation are
listed for Al, Cu and Mg atoms below
Al Cu Mg
? 5 5 6
? 10.5 8.5 10.5
? 20 20 20
rc 1.9 1.9 1.7
?e 0.12538 0.36952 0.14720
a -4.8144 -4.0956 -1.1049
b 0.47685 -1.6979 -1.3122
?e 12.793 12.793 12.316
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CONSTRUCTION OF COMPUTATIONAL CRYSTAL
CONSTRUCTION OF COMPUTATIONAL CRYSTAL
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BOUNDARY CONDITIONS FOR GB SLIDING
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3 GB Sliding and Migration at 500K (Applied Shear)
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Mg
Al
y
GB
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Energy distribution at grain boundaries
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Note
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Radius Distribution Function (RDF)
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