Dislocation junctions and jogs in a free-standing FCC thin film
نویسندگان
چکیده
Dislocation junctions and jogs in a free-standing FCC thin film have been studied using 3dimensional dislocation dynamics simulations. Due to the unconstrained motion of surface nodes and dislocation annihilation at the free surface, junctions and jogs are unstable except for some uncommon conditions. If the film thickness is thin enough for a significant portion of dislocation network to be terminated at the free surface, junctions and jogs can exist for only a finite time during deformation. Thus, the creation of junction/jog-related dislocation sources and their performance are more limited as the film thickness decreases. This effect could lead to insufficient dislocation multiplication to balance dislocation annihilation at the free surface.
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