Mechanism of strain hardening and dislocation-structure formation in metals subjected to severe plastic deformation

作者：Malygin GA^*

来源：Physics of the Solid State, 2006, 48(4): 693-699.

DOI：10.1134/S1063783406040123

The equations of dislocation kinetics are used to theoretically analyze the mechanism of strain hardening and the formation of fragmented dislocation structures in metals at large plastic strains. A quantitative analysis of the available data on aluminum and an aluminum-magnesium alloy shows that strain hardening at large plastic strains and the formation of fragmented dislocation structures are related to the interaction and self-organization of geometrically necessary dislocations (GNDs). On the microscale, the source of the GNDs is a locally nonuniform plastic deformation induced by a dislocation-density gradient in dislocation-cell boundaries.