Effect of bimodal microstructure on texture evolution and mechanical properties of 1050 Al alloy processed through severe plastic deformation and subsequent annealing

In this study, aluminium sheets were processed through 8 cycles of accumulative roll bonding (ARB), and then, were annealed at 300 degrees C for different time periods to maintain the optimum annealing process for the formation of bimodal microstructure. Variations in microstructure, texture, and mechanical properties were studied using optical microscopy (OM), X-Ray diffraction (XRD), and hardness and uniaxial tensile tests. Microstructural observations showed that recrystallized grains formed after 10 s of annealing; however, recovery occurred after 1 s due to the high stacking fault energy (SFE) of aluminium. Fully recrystallized microstructure was seen after 900 s. A bimodal grain size was achieved after 3600 s and the ratio of the average size of the largest 2% grains to mean grain size (dmax/ d d d ratio of 3 was the main reason for this phenomenon.

Automated summary

Aluminium sheets were processed through 8 cycles of accumulative roll bonding and then annealed at 300 degrees C for different time periods to achieve bimodal microstructure. The microstructural observations showed recrystallized grains forming after 10 s, full recrystallization after 900 s, and a bimodal grain size after 3600 s. The ratio of the average size of the largest 2% grains to mean grain size was the main reason for this phenomenon.