If dislocations of opposite sign are able to change their slip plane, they can annihilate each other and cause a decrease of the strain hardening rate. This phenomenon is referred to as dynamic recovery.

Edge dislocations move perpendicular to their glide plane by absorption or emission of vacancies. This process is called climb.

Screw dislocations cause dynamic recovery by changing to another slip plane through cross slip.

In the simulation below, observe how enabling edge dislocations to change slip plane by climb significantly reduces the number of dislocations after a given time. See what happens if you check 'Opposite dislocations' and enable climb.