Dynamic recrystallization during hot torsion of Al-9Mg alloy
(State Key Laboratory for Advanced Metals and Materials; University of Science and Technology Beijing; Beijing 100083; P. R. China；
Beijing Institute of Technology; Beijing 100083; P. R. China)
Beijing Institute of Technology; Beijing 100083; P. R. China)
Abstract: Specimens of single phase Al-9Mg alloy have been deformed by hot torsion at 300 450 t and strain rates of 0. 005 1. 587 s-1 to true strain of 5. 5 folowed by water quenching immediately. The dynamic restoration mechanisms during hot torsion were examined by the true stress-true strain curves, optical and electron microscopy. It has been shown that dynamic recrystallization occurs and the dynamic recrystallization behaviour is sindlar to that of those materials with a low stacking fault energy. The microstructural observations indicate that a large number of dislocations appear in a certain crystallographic orientation in the dynamically recrystallized grains. High resolution streak images show that the very fine reqions of stacking faults exist in the matrix of Al-9Mg alloy.
Key words: Al-9Mg alloy; dynamic recrystallization; torsion; stacking faults