Early-Stage Dislocation Structures inside the Dislocation Channels of Face-Centered-Cubic Metals with Point Defect Clusters Running Head: Dislocation Structures inside Dislocation Channels

Early-stage dislocation structures inside dislocation channels of rapid-cooled and tensile-deformed aluminum single crystals were investigated by using the bright field imaging mode in a scanning transmission electron microscope (STEM-BF). Inside dislocation channels, arrays of the prismatic dislocation loops originated from dislocations of the primary slip system, i.e.,(1 1 1)[1 ത0 1], were mainly formed. Dislocations of the primary coplanar slip systems such as (1 1 1)[0 1 1 ത] and (1 1 1)[1 ത1 0] were activated owing to internal stresses caused by the primary dislocations pile-up inside the cleared channels. The activated primary coplanar dislocations left the dislocation loops elongating along the edge dislocation directions behind them. Inter-dislocation-loop interactions occur especially at the arrays of the prismatic dislocation loops originated from dislocations of the primary slip systems and produce b utter fly sha pe dislocation loops. As the but terfly shape dislocation loops have s es si le junctions, they should act as obst acles against the following multiplications and glides of the dislocations. When the interactions proceed, t angle d struct ure s would be formed around the arrays of the prismatic dislocation loops originated from dislocations of the primary slip system.

Automated summary

Early-stage dislocation structures inside dislocation channels of rapidly cooled and tensile-deformed aluminum single crystals were investigated using STEM-BF. Prismatic dislocation loops originated from dislocations of the primary slip system were mainly formed inside dislocation channels. Interactions between dislocation loops produced butterfly-shaped dislocation loops, which act as obstacles to subsequent dislocation multiplication and glide. Angled structures would be formed around the arrays of prismatic dislocation loops originated from dislocations of the primary slip system.