Dislocation field evolution and dislocation source/sink function

The evolution of dislocation density ield depends on the source/sink function; this function describes the nucleation of new dislocations and the coalescence processes (mutual annihilation of dislocations having the opposite signs which is equivalent to coalescence of two neighbouring dislocated elements or coalescence of two co-planar cracks). In this paper we discuss the choice of this function, we present the solutions for dislocation field and stresses and we discuss the obtained results, especially the short period perturbations (seismic events) related to the extrema and sign changes of the source/sink function. General discussion on the source/sink function for dislocation fields closes this paper.