| Abstract |
| High temperature deformation behavior of AZ31 Mg alloy was investigated in this study on the basis of a processing map (ε = 0.6). To construct a processing map, compression tests were carried out at wide range of temperatures and strain rates (T=250-500℃, ε˙=10^(-4)-100/s). Two regions of high deformation efficiency (η) were identified as: (1) a dynamic reciystalization (DRX) domain at 250℃ and 1/s and (2) a superplasticity domain at 450℃ and 10^(-4)/s. The average grain size of the specimens deformed in the DRX region was smaller than those of deformed in any other regions. In the superplastic condition, tensile elongation to failure approached to 1040%. The results of compression tests showed that 10 of log Z (Zener-Hollomon parameters) was the boundary of flow softening and hardening. At the high Z (above 10^(10) of Z) regions, flow softening occurred accompanying the dynamic recrystallization, while at the low Z (below 10^(10) of Z) regions, flow hardening occurred due to the grain growth. Possible deformation mechanisms operating at high temperature were discussed in relation to the activation energy. |
|
|
| Key Words |
| AZ31 Mg alloy, Formability, Processing map, Superplasticity, Dynamic recrystallization |
|
|
 |
|
