.7050 Aluminum Alloy High Temperature Rheological Behavior

7050 aluminum alloy is a kind of aerial structural matrial with high strength and toughness, which can be applied widely in manufacture of aircraft main structures. The flow stress model during high temperature of 7050 aluminum alloy is important theoretical foundations for research of forging technics with structures of 7050 aluminum alloy.The deformation behaviors for 7050 aluminum alloy at high temperatures have been investigated with Gleeble-1500 thermal simulator. The interrelations of flow stress , strain rate, strain and deformation for 7050 aluminum alloy during high temperature deformation have been studied with the aid of regression analysis.Also the flow stress model of the alloy has been found; Integrating the flow stress equation model into the FE code of Deform3D, the effect of hot deformation parameters, such as the deformation temperature and deformation velocity, on the equivalent stress, the equivalent strain, the load and the microstructural evolution of the material during hot deformation has been studied; The characteristic of microsturcture and dynamic recovery and dynamic recrystallization phenomenon of the alloy have also been discussed with the aids of OM, SEM, EDAX.The study shows as followed: Grain-boundary segregation with the original test sample of 7050 aluminum alloy was improved after uniform heat treatment. A steady state of plastic flow of the 7050 aluminum alloy was confirmed during compression deformation at high temperature.The stress at steady state of plastic flow decreased with the increase of deformation temperature and increased with the increase of strain rate. Dynamic recovery and dynamic recrystallization occur obviously during hot compression of 7050 aluminum alloy. It was found that when the temperature is lower than 400^C and the strain rate is higher than ls^-1, dynamic recovery took place in 7050 aluminum alloy, and formed the relative steady grains; With the increase of temperature, the microstructural structure was more completely and the boundary was more definite. When the temperature is higher than 400^C, the strain rate is lower than 1 s⁽-1_, dynamic recrystallization phenomenon took place in 7050 aluminum alloy. Different technical parameters like the deformation degree, the deformation temperature and the deformation velocity can cause effect on nucleation and grain growth of recrystallization with 7050 aluminum alloy.Reseach result of the text can be theoretical base of technical reseach of 7050's large structures.