Effect of Deformation Annealing on Microstructure, Texture and Properties of 2A12 Aluminum Alloy

Abstract:

The effects of different deformation annealing processes on the microstructure, texture, and properties of 2A12 aluminum alloy were studied by scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS) and electron backscatter diffraction (EBSD). Results demonstrate that after deformation annealing treatment, the 2A12 aluminum alloy grains become longer along the rolling path and smaller in size. The proportion of subgrain boundaries decreases, the proportion of low angle grain boundaries (LAGB) at 2°?15° increases, and the proportion of high angle grain boundaries (HAGB, >15°) first increases and then declines as the deformation annealing treatment cycles increase. The degree of recrystallization rises at this point as the annealing process switches from recovery multi-lateralization to recrystallization. After single-step deformation annealing, the two samples have a similar microstructure and proportion of HAGB and LAGB in total due to the small deformation and less deformation stored energy. Compared to the sample that underwent mild deformation with the same annealing process, the large deformation sample has a lower proportion of subgrain boundaries in total and a higher proportion of LAGBs and HAGBs, and the degree of recrystallization increases. There will be texture evolution pathways of Brass→R-Cu and m-Brass→Goss→R-Goss→Cube, T and P_0°→Near rotated Cube and {102}<201> when the deformation is significant. R-Cu and m-Brass→Goss→R-Cube will become the new route during single-step small deformation annealing. The toughness and plasticity of the 2A12 aluminum alloy diminish while the strength and hardness rise with higher deformation.

Key words:2A12 aluminum alloy;deformation annealing;mechanical properties;corrosion property;texture