Constitutive model and processing maps of 7055 aluminum alloy used for fasteners

The hot deformation behavior of an annealed 7055 aluminum alloy was investigated by isothermal compression tests over the temperatures range of 250-450 degrees C and strain rates range of 0.001-10 s-1. The true stress-strain curves were obtained by applying friction and temperature corrections to experimental data. Based on the corrected curves, a sixth-order polynomial Arrhenius-type constitutive equation is established to represent the material characteristic constants. To investigate the workability of this material, processing maps representing the power dissipation capacity with examining various strains were created. According to the processing maps and examination of microstructures, the recommended processing parameters were within the temperatures range of 300-400 celcius and strain rates range of 10- 1.5-1 s-1, a good workability and uniformly deformed grains can be obtained under this condition. The preponderant softening mechanism is DRV (dynamic recovery) over all the recommended deformation parameter domains, but the effect of DRX (dynamic recrystallization) is enhanced in regions of low strain rate and high temperature deformation.

Automated summary

The hot deformation behavior of an annealed 7055 aluminum alloy was studied through isothermal compression tests. A constitutive equation was established and processing maps were created to determine the recommended processing parameters. Good workability and uniform deformation grains can be achieved under the temperature range of 300-400 degrees Celsius and strain rates range of 10- 1.5-1 s-1. The dominant softening mechanism is dynamic recovery, with the effect of dynamic recrystallization enhanced in regions of low strain rate and high temperature deformation.