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., ð111Þ½101 , were mainly formed.
Dislocations of the primary coplanar slip systems such as ð111Þ½0 1 1 and ð111Þ½110 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 “butterfly shape” dislocation loops. As the “butterfly shape” dislocation loops have “sessile”
junctions, they should act as “obstacles” against the following multiplications and glides of the dislocations.