Plastic Deformation

· The fcc lattice is formed by the stacking of the close packed
{1 1 1 } planes following the sequence:
..........ABCABCABCABC.........
· The slip displacement associated with a unit dislocation moving over the slip plane takes planes above the slip plane to new locations.
· After slip (or Glide) the unit dislocation has taken:
A -> A ; B -> B ; C ->C
and the planes are stable in their new locations.
· Other possible slip vectors on the slip plane can take the other planes to different stable locations. These slip vectors are associated with Shockley "partial dislocations" which have smaller Burgers vectors than the Unit dislocation: b_S= (a/6)<211>