The dislocation density 200 micrometres into the surface of a material has been shown to be six times higher than the density in the bulk.

Since strain hardening is related to an increased dislocation density, reducing the number of dislocations reduces strength.

This process can be further modified to reduce dislocation densities.

Since the dislocation density increases with plastic deformation, a mechanism for the creation of dislocations must be activated in the material.

The process produces dislocation densities up to 10/cm.

The effects of cold working may be reversed by annealing the material at high temperatures where recovery and recrystallization reduce the dislocation density.

The interiors of the cells have a correspondingly reduced dislocation density.

Increasing the dislocation density increases the yield strength which results in a higher shear stress required to move the dislocations.

At dislocation densities of 10 dislocations/m or higher, the strength of the material becomes high once again.

It should be noted that the dislocation density can't be infinitely high because then the material would lose its crystalline structure.