Effect of scandium on superplasticity of Al-Mg alloys
(1. College of Metal Forming, Material and Metallurgy,
Northeastern University, Shenyang 110006, P.R.China;
2. The Capital Iron and Steel Company, Beijing 100083, P.R.China)
Northeastern University, Shenyang 110006, P.R.China;
2. The Capital Iron and Steel Company, Beijing 100083, P.R.China)
Abstract: The superplastic behavior of adding 0.22%Sc into the Al-6Mg alloy was studied by simple superplastic pretreatment process--warm rolling and cold rolling. The optimum superplastic temperature and strain rate of the alloys were defined and satisfactory results were obtained during the superplastic deformation at 811 K and initial strain rate ε0=1.67×10-3s-1. The average elongation of Al-6Mg-0.22Sc alloys reaches to 1 125%, and the maximum elongation is 1 200%, maximum m value (strain rate sensitive index) is 0.879. But under the same condition the elongation and maximum m value for Al-6Mg alloy were only 377% and 0.595, respectively. The superplastic deforming mechanism for Al-6Mg-0.22Sc alloys was also discussed.
Key words: Al-6Mg-0.22Sc alloy; Al-Mg alloy; superplasticity