.7050 Aluminum Alloy High Temperature Deformation Behavior Of Experimental Research

Isothermal compression tests of 7050 aluminum alloy were performed on Gleeble-1500 thermal simulator. Regression analysis, optical microscope(OM) and transmission electron microscope(TEM) were employed to analyze the deformation behavior and the microstructure evolution of 7050 aluminum alloy on different deformation conditions. The main contents are as follows:The stress-strain curves and the flow stress equation of 7050 aluminum alloy using laboratory material and factory material were obtained by the thermo-compression tests carried out in the deformation range of 50%,60% and 70% , temperature range of 250℃- 450℃and strain rate range of 0.01 s^-1-10s^-1 .The results show that the peak stress using the laboratory material is higher than using the factory material. The stress-strain curves using the laboratory material can achieve the peak stress quicker than using the factory material. The flow stress decreased with the increase of deformation temperature and increased with the increase of strain rate. When the deformation reach the definite value under the same temperature and strain rate, the flow stress would not change with the deformation.The optical microscope(OM) and transmission electron microscope(TEM) were employed to analyze the microstructure of the 7050 aluminum alloy. The analyses results show that there are more dynamic recrystallization grains using the laboratory material than using the factory material. The distribution of the dynamic recrystallization grain is more uniform using the laboratory material than using the factory material. The hot deformation parameters have a great influence on the microstructure of the 7050 aluminum alloy. The dislocation density decreases with the increase of the deformation temperature, while it increases with the increase of the strain rate. The mean sub-grain size increases with the increase of the deformation temperature and the decrease of the strain rate. The increase of the deformation and temperature , and the decrease of the strain rate are beneficial to the dynamic recrystallization.