A dynamic dislocation description was presented of the plastic strain localization and mesoscopic dislocation patterning which were associated with persistent slip bands in fatigued face-centered cubic metals. The analysis concentrated on the densities and height distributions of edge dislocation dipoles which formed under conditions of cyclic stress saturation. Various dislocation mechanisms were assumed to govern the operation of a persistent slip band. Thus, glide-induced dipole decomposition was important for establishing steady-state conditions during cyclic saturation. Small pile-ups, of 3 to 4 edge dislocations, led to yielding of the persistent slip band walls. When these processes were taken into account, quantitative agreement was obtained with experimental observations of Ni single crystals which had been fatigued at temperatures ranging from 77 to 750K.

On the Dislocation Dynamics of Persistent Slip Bands in Cyclically Deformed FCC Metals P.Hähner, B.Tippelt, C.Holste: Acta Materialia, 1998, 46[14], 5073-84