Quasi-in-situ electron backscattered diffraction investigation of twin-induced recrystallization during electrical pulse treatment in AZ61 alloy

Abstract

In this work, static recrystallization induced by deformations twins in cryogenic rolled AZ61 alloy during electric pulse treatment is investigated by using quasi-in-situ electron backscattered diffraction. Besides of the {10 1- 2} tensile twins, {10 1- 1} compression twins, {10 1- 2}-{10 1- 1} double twins are also observed in the as-deformed AZ61 alloy. It has been found that recrystallization occurs preferentially at the early stage of electric pulse treatment, with {10 1- 2}-{10 1- 1} double twins and {10 1- 1} compression twins being effective nucleation sites for recrystallization. In contrast, lenticular {10 1- 2} tensile twins are consumed by surrounding grains that are with growth advantage. Our results suggest a feasible way to tailor the microstructure of Mg alloys through cryogenic rolling and electrical pulse accelerated recrystallization.