DYNAMIC RECRYSTALLIZATION AND DYNAMIC RECOVERY IN PURE ALUMINUM AT 583 K

In situ observations using transmission Laue X-ray photographs taken during 583 K compression tests were used to compare the restorative process of 99.999 mass% aluminum to that of 99.99 mass% aluminum. A regular multipeak stress oscillation, typical of dynamic recrystallization, was generated in 99.999 mass% aluminum, while monotonous work hardening, typical of dynamic recovery, were present in 99.99 mass% aluminum. Spot patterns as well as coarse recrystallized grains containing subgrains confirmed dynamic recrystallization in the 99.999 mass% aluminum. The dynamic recovery of 99.99 mass% aluminum was confirmed by asterism patterns and equiaxed subgrains. Dynamic recrystallization was found to take place only in the high purity range above 99.999 mass%. This dynamic recrystallization was considered to be the results of discontinuous dynamic recrystallization which is well known in Cu, Ni and gamma-Fe.