Dislocation-Disclination Substructures Formed in FCC Polycrystals Under Large Plastic Deformations: Evolution and Association with Flow Stress

The evolution of dislocation substructures formed in polycrystalline Cu−Al and Cu−Mn alloys undergoing large plastic deformations is studied, using transmission electron microscopy. Microband and fragmented substructures are examined. The Al and Mn alloying element concentrations for which the substructures are formed have been found. The mechanisms involved in the formation of the substructures during the substructural evolution in the alloys subjected to deformation have been revealed. Parameters describing the substructures under study have been measured. The dependence of the parameters on the flow stress has been established.