Describe the microstructure of a heavily cold-worked metal of an Al–0.8% Mg alloy as observed with..

Describe the microstructure of a heavily cold-worked metal of an Al–0.8% Mg alloy as observed with an optical microscope at 100× (see Fig. 6.46a). Describe the microstructure of the same material at 20,000× (see Fig. 6.47a).