Strain rate effects on microstructure and texture evolution in cold-sheared Al-6 Mg alloys during low-temperature annealing

This study examined the effects of the strain rate on the texture evolution of Al-6Mg alloys over one hour of annealing at 300 degrees C. Three different strain rates of 0.1 s(-1) , 1 s(-1) , and 10 s(-1) were applied to the samples using a torsion tester. Considerable grain growth was observed in the 0.1 s(-1) cold-sheared sample during one hour of annealing. The growth of B/B and C-oriented grains can explain the grain coarsening behavior. The conventional grain growth, nucleation, and subsequent grain growth, plausibly describe the grain size evolution of those 1 s(-1) and 10 s(-1) cold-sheared samples during annealing. A textural transition from brass type to copper-type was evident during the annealing process of the 1 s(-1) cold-sheared sample. On the other hand, the brass-type texture bias in the 10 s(-1) cold-sheared sample increased gradually over one hour of annealing. The copper-type texture generally evolved under the 0.1 s(-1) cold-sheared condition. Generally, the misorientation indices (= M-index) of all three cold-sheared samples were decreased by extending the annealing time. A smaller M-index indicates stronger texture anisotropy. Although the M-index was higher in the 0.1 s(-1) and 10 s(-1) cold-sheared samples than the 1 s(-1) sample throughout the annealing process, the M-index of the 0.1 s(-1) sample eventually became the lowest among the three conditions under the fully annealed condition. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study investigated the effects of strain rate on the texture evolution of Al-6Mg alloys during one hour of annealing at 300 degrees C. Grain growth was significant in the 0.1 s(-1) cold-sheared sample, while a texture transition from brass type to copper type was observed in the 1 s(-1) sample. The misorientation indices of all samples decreased with annealing time, indicating a stronger texture anisotropy.