Editing Dislocation (section)

=== Jog ===
[[File:Jog-Kink.gif|thumb|right|Geometrical differences between jogs and kinks]]
A '''Jog''' describes the steps of a dislocation line that are not in the [[glide plane]] of a [[crystal structure]].<ref name=Föll/> A dislocation line is rarely uniformly straight, often containing many curves and steps that can impede or facilitate dislocation movement by acting as pinpoints or nucleation points respectively. Because jogs are out of the glide plane, under shear they cannot move by glide (movement along the glide plane). They instead must rely on vacancy diffusion facilitated climb to move through the lattice.<ref>{{cite book|first=W.|last1=Cai|first2=W. D.|last2=Nix|title=Imperfections in crystalline solids|location=Cambridge, UK|publisher=Cambridge University Press|year=2016}}</ref> Away from the melting point of a material, vacancy diffusion is a slow process, so jogs act as immobile barriers at room temperature for most metals.<ref name="courtney00">{{cite book|first=T. H.|last=Courtney|title=Mechanical behavior of materials|location=Long Grove, IL|publisher=Waveland|year=2000}}</ref>

Jogs typically form when two non-parallel dislocations cross during slip. The presence of jogs in a material increases its [[yield strength]] by preventing easy glide of dislocations. A pair of immobile jogs in a dislocation will act as a [[Frank–Read source]] under shear, increasing the overall dislocation density of a material.<ref name="courtney00" /> When a material's yield strength is increased via dislocation density increase, particularly when done by mechanical work, it is called [[work hardening]]. At high temperatures, vacancy facilitated movement of jogs becomes a much faster process, diminishing their overall effectiveness in impeding dislocation movement.