SIT Internal
EDGE DISLOCATION OF PURE METAL
PERFECT LATTICE
EDGE DISLOCATION
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SIT Internal
(i)
EDGE DISLOCATION MOTION OF PURE METAL
Edge dislocation move in the direction of red arrow
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(ii)
Edge dislocation at new location. Notice the strain
field has move from left to right
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SIT Internal
EDGE DISLOCATION OF PURE METAL
EDGE DISLOCATION OF METAL WITH SMALL SOLUTE ATOMS
For small solute atoms, they tend to substitute into
the compressive region of dislocation stress field
(blue). This help to lower the strain field of the
dislocation.
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SIT Internal
(i)
SMALL SOLUTE ATOMS – DISLOCATION MOTION
Edge dislocation move in the direction of red arrow
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(ii)
Edge dislocation at new location. Notice the strain
field associated with dislocation field has move from
left to right. It is larger now compared to the strain
field when dislocation is with small solute atoms. i.e.
see (i).
Also notice the small solute atoms now do not have a
dislocation, but due to its smaller size, it also generate
a strain field due to distortion to the lattice.
Overall, the strain field in (ii) is bigger than (i).
Compare that to the slide 2 (pure metal)
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SIT Internal
EDGE DISLOCATION OF PURE METAL
EDGE DISLOCATION OF METAL WITH BIG SOLUTE ATOMS
For large solute atoms, they tend to substitute into
the tensile region of dislocation stress field (orange).
This help to lower the strain field of the dislocation.
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SIT Internal
(i)
BIG SOLUTE ATOMS – DISLOCATION MOTION
Edge dislocation move in the direction of red arrow
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(ii)
Edge dislocation at new location. Notice the strain
field associated with dislocation field has move from
left to right. It is larger now compared to the strain
field when dislocation is with big solute atoms i.e. see
(i).
Also notice the large solute atoms now do not have a
dislocation, but due to its larger size, it also generate a
strain field due to distortion to the lattice.
Overall, the strain field in (ii) is bigger than (i).
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