Materials Science Forum, Vol.396-4, 487-492, 2002
Comparison of recrystallisation behaviour of AA5052 after hot deformation in reversed torsion and in compression/tension
During industrial hot working operations, such as rolling, forging and extrusion, regions of the workpieces undergo a change in strain path. A significant effect of change in straining direction in tension/compression deformation, which is the simplest change in strain path, on microstructural evolution and subsequent recrystallisation behaviour of aluminium-magnesium alloys has been found in previous research. The present paper shows the experimental results on the effect of change in straining direction of shear deformation on the microstructural evolution and subsequent recrystallisation behaviour, in comparison with those after axisymmetric deformation. The shear deformation was carried out in a torsion testing machine and the axisymmetric deformation in a tension/compression testing machine using the same alloy. Experimental results show a significant effect of change in straining direction on subsequent recrystallisation behaviour of AA5052 in axisymmetric deformation, but not in torsion. The mechanism of this difference may be related to the different microband behaviour in the axisymmetric and shear deformations, i.e. a higher density of microbands in the former, or a different texture evolution.