HOT DEFORMATION BEHAVIOR OF AN Al-7.6Zn-l.8Mg-l.4Cu-0.12Zr ALLOY

摘要

To meet the stringent requirements of ultra-thick section products for aerospace applications, an Al-7.6Zn-l.8Mg-l.4Cu-0.12Zr alloy with good performance was developed. The behavior of the alloy during hot deformation was studied by isothermal compression in the temperature range from 250°C to 450°C and strain rate from 0.001 s~(-1) to 10 s~(-1) on Gleeble-1500D thermal mechanical simulator. And the EBSD and TEM were employed to analyze the microstructure of the alloy treated by different deformation processes. The results show that the flow stress of the alloy during hot compression deformation decreases with the increase of the deformation temperature, and increases with the increase of the strain rate. The flow stress can be described by using Zener-Hollomon parameter including Arrhenius item. The microstructure evolution is significantly influenced by both deformation temperatures and strain rates.