Plastic Deformation

· Edge dislocations can move normal to a slip plane by diffusion controlled "climb." Diffusion rates increase exponentially with increasing absolute temperature, and this is an important high temperature recovery mechanism.

· A tensile stress component normal to the extra half plane can aid the climb process by providing a force component: F_Climb = σb per unit length. The stress will have contributions from other dislocations.
· The stress provides a chemical potential gradient that enhances the diffusion flux to the dislocation.