A model was developed for dislocation dynamics, in single-glide oriented face-centered cubic or hexagonal close-packed monocrystals, during cyclic plastic deformation. Evolution equations were derived for the densities of both mobile dislocations and immobile dislocation dipoles. In addition, account was taken of the temporal evolution of the density of point-defect agglomerates that were formed as a result of the annihilation of close edge-dislocation dipoles. It was assumed that the internal stresses which gave rise to the athermal component of the flow stress originated mainly from dislocation dipoles, and that the thermal flow-stress component resulted from the overcoming of point-defect agglomerates which acted as local dislocation obstacles. The mathematical description of cyclic hardening which resulted from this picture was applied to strain amplitude-controlled cyclic deformation.

Dislocation Dynamics in Cyclic Plastic Deformation – I. Monotonic Hardening. M.Zaiser, W.Frank: Applied Physics A, 1995, 60[5], 497-503