摘要
The isothermal compression tests of 7085 aluminum alloy were carried out on Gleeble-3800 thermal simulator by two-pass(30%per-pass)and three-pass(20%per-pass)at 300-400℃and the strain rate of 0.01 s^(-1).The effect of compression strategy on microstructure evolution of 7085 aluminum alloy was analyzed by optical microscopy(OM)and electron backscattering diffraction(EBSD).The results show the softening mechanism of 7085 aluminum alloy is mainly recovery,the recrystallization degree is sluggish when the samples deform at 300℃.The fraction of recrystallized grains just reaches 23.2%at a higher deformation temperature of 400℃,while a large amount of sub-grains with equiaxed morphology are formed inside the deformed grains.Different deformation paths have a significant effect on the microstructure evolution of the 7085 aluminum alloys,and more uniform and fine microstructures are obtained at the three-pass deformation.In addition,a short holding time of 5 s is not enough to trigger the static recrystallization.When the holding time reaches 120 s,the dislocations rearrange and a large number of recrystallized grains and regular sub-grains appear inside the original grain.In a word,more uniform and fine microstructures are obtained at three-pass deformation at 400℃and 120 s of 7085 aluminum alloy.
基金
by the Key Research and Development Project of Shanxi Province(201903D121040)
the Fundamental Research Program of Shanxi Province(202103021224282 and 202103021223288)
the Science and Technology Innovation Project of Higher Education in Shanxi Province(2020L0331 and 2020L0341)。