Hot deformation behavior and processing map of aluminum alloy 2D70

The isothermal compression tests with constant strain rate for aluminum alloy 2D70 were conducted by THERMECMASTOR-Z hot simulator. The hot deformation behaviors in the temperature range of 320-530 ℃ and the strain rate range of 0.001-70.0 s-1 were investigated. Then, the processing maps under these deformation conditions were constructed and the deformation thermomechanical parameters were then optimized based on the generated processing maps. The results show that the flow instability zone increases with true strain increasing during the hot deformation process. Otherwise, when the strain rate is higher than 1.0 s-1, most of the deformation behavior is located at the flow instable zone. Under this condition, the domain of flow localization appears at the temperature lower than 350 ℃ and mechanical instability exhibits at the temperature higher than 500 ℃. While, when the strain rate is lower than 0.1 s-1 and the temperature is lower than 350 ℃, the wedge cracking can be found. On the base of the experimental results including processing map and microstructure, the optimum deformation thermomechanical parameter ranges of aluminum alloy 2D70 can be confirmed to the temperature range of 370-460 ℃ and the strain rate range of 0.004-0.1 s-1.