Dislocation cell structures formed inside dislocation channels of rapid-cooled and tensile-deformed aluminum single crystals

Dislocation cell structures inside the cleared dislocation channels in rapid-cooled and tensile-deformed aluminum single crystals were investigated by using transmission electron microscope (TEM). Inside the dislocation channels, dislocation network structures lying on multiple planes were forming the cell structures. One of the planes on which the networks were lying was the primary slip plane, i.e., (1 1 1) plane. Since the Burgers vectors of the dislocations composing the networks were identified as parallel to [1 0 1][0 1 1] and [1 1 0], the networks were creating the crystallographic rotation of which twisting axis was parallel to the normal direction of the cross slip plane, i.e., [1 1 1] plane. Through the quasi-continuous 3D moving images, these cell structures consisting of the network structures on multiple planes were recognized as "cocoon-like"closure shaped and developed along the primary dislocation channels. Since these structures were consisting of the primary dislocations and the secondary dislocations which were considered to be activated due to the pile-ups of the primary dislocations and distributing independently, origin of the formation of the structures were not "incidental"nor "geometrically necessary"but rather "energetically necessary"driven.