Distribution characterization of boundary misorientation angle of 7050 aluminum alloy after high-temperature compression

Compression tests of 7050 aluminum alloy have been conducted at different temperatures (340, 380, 420, and 460 °C) and different strain rates of 0.1, 1, 10, and 100 s^-1. The microstructure characteristics of the alloy after deformation are investigated using OM, electron backscatter diffraction (EBSD) technique and TEM. Results show that the volume fraction of recrystallized grains and the average misorientation angle increase with the increase of deformation temperature with the strain rate of 0.1 s^-1. When the 7050 aluminum alloys were deformed at 460 °C, the volume fraction of recrystallized grains and average misorientation angle decrease with increasing strain rate. The primary softening mechanism of the 7050 aluminum alloy deformed at 340, 380, and 420 °C with the strain rate of 0.1 s^-1 is dynamic recovery. Dynamic recrystallization is the main softening mechanism of the alloy deformed at 460 °C and different strain rates. The softening mechanism of the alloy is not sensitive to strain rate.