Relationship between Formation of Geometrically Necessary Dislocations and Local Strain Hardening of Slip Systems in Symmetric Type Bicrystals under Tensile Loading

Abstract

Slip deformation in symmetric-type bicrystal models subjected to tensile load is investigated by a finite element crystal plasticity analysis code. Accumulation of geometrically necessary dislocations (GNDs) and statistically stored dislocations (SSDs) are studied in detail. Some results of the analysis show local strain hardening of slip systems and activity of secondary slip systems with accumulation of GNDs on primary slip system in the form of band. Mechanism of local strain hardening of primary slip systems in symmetric-type bicrystals is discussed from the viewpoint of dislocation interaction between primary and secondary slip systems and effects of high density pattern formation of GNDs on primary slip system.