Dislocation Structure in Hot Deformed Al-Zn-Mg Alloy by X-ray Line Profile Analysis.

The microstructure of extruded Cu-free Al-Zn-Mg alloy is studied. Hot torsion tests are performed on a Cu-free Al-Zn-Mg alloy to investigate the effect of large strain deformation on the dislocation behavior. The dislocation structure is characterized by X-ray diffraction profile analysis, and the effective stress-strain curves are obtained by hot torsion tests. The dislocation density at low deformation temperature is found to be higher than that at high deformation temperature. The dislocation density of the alloy increases gradually up to epsilon = 1 with increasing strain and does not change significantly during further deformation.