In the present study, the formability of Mg-AI-Zn alloy sheets containing 2. 0-4. 5 percent AI and 0.7-1.5 percent Zn (AI:Zn=3:1) were investigated at elevated temperatures by carrying out various experiments. To examine the mechanical properties of the sheets, uniaxial tensile tests were conducted at different temperatures and strain rates. The formability of the alloys was evaluated by limit drawing ratio (LOR) tests and limit dome height (LOH) tests at given conditions. The experiment results indicate that the LOR increases remarkably with temperature and reaches the maximum value at 498K. The results also show that the LOR of the alloys at 498K is improved with increasing AI and Zn contents and obtaining the peak at 3 percentAI. The LOR of the sheets is decreased with respect to the content of All over 3 percent. This could be due to the dynamic recrystallation occurs during forming process. As a result, LOR of Mg-3 percent Al-1 percent Zn reaches 3.2 while LOR of Mg-4.5 percent AI-1.5 percent Zn decreases to 2.8. Another aspect was,also found out that the as-rolled specimens (F-specimens), containing large residual working strain, exhibit higher formability as compared to the annealed specimens. In the stretch forming, the F-specimens also show excellent stretching formability.
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