Figure 1.
Illustration of conjugate channeling effect in dislocation core diffusion.
Black arrows indicate the carbon diffusion path through bulk lattice (O-site) along and black dots indicate the O-site along the path. Red arrows indicate the carbon diffusion path through dislocation core along
.
is the maximum dislocation core length which can be dragged by single carbon atom (See text for details). The dislocation loop is located between
th and
+1th plane as shown in upper right figure. Lower right figure show the relation between conjugate diffusion vector c and Burgers vector b.
Figure 2.
Temperature dependence of carbon diffusivity, in
-iron.
MD and accelerated MD (AB) [14] results are displayed with filled and open symbols, respectively. One-carbon diffusivity results in bulk lattice, in fixed edge dislocation core, in free edge dislocation core are displayed with circles, squares, and triangles, respectively. Two-carbon diffusivity result in free dislocation are displayed with diamonds. The lines are polynomial fits as guide to the eye.
Figure 3.
Temperature dependence of (a) activation enthalpy and (b) activation entropy of one-carbon diffusivity in free edge dislocation core.
Figure 4.
Conjugate diffusion avenue in edge dislocation core.
Blue and green dots indicate the atoms on th and
+1th
planes, respectively. Red dashed lines indicate the conjugate diffusion avenue in the dislocation core, a channel as wide as possible (
is one of the two widest avenues on a plane) and as tall as possible (a full
interplanar spacing) in a BCC crystal.
Figure 5.
Geometries of (a) curved dislocation core, (b) screw dislocation core, and (c) 71° mixed dislocation core along .
Blue and green dots indicate the atoms on th and
+1th
planes, respectively. Black lines are the eye guides for the dislocation cores. Red dashed lines indicate the conjugate diffusion avenue along
in the dislocation core, a channel as wide as possible (
is one of the two widest avenues on a plane) and as tall as possible (a full
interplanar spacing) in a BCC crystal.