PNNL

Abstract

The configuration of dislocation wall structure and the interactions between dislocation and dislocation wall play a significant role on the understanding of deformation process in aluminum. Transmission electron microscopy TEM) was used to provide valuable information on dislocation microstructure which is critical for theoretic modeling of dislocation dynamics during plastic deformation. Samples of single crystal aluminum deformed by tensile-straining (15%) or poly-crystal aluminum deformed by channel-die compression were analyzed using TEM. The detailed analysis of Burgers vectors for dislocations in the dislocation cell boundary were utilized. In tensile deformed (15%) single crystal aluminum, cell structure is well developed and dislocations in the cell boundaries consist of either one type of Burgers vector or multiple types of Burgers vector. Channel-die compressed sample at strain of 1.2% already show the densely tangled dislocation structure. The preliminary result on in-situ deformation on the dislocation interaction with cell wall structure will be discussed.