The dynamic recrystallization and mechanical property responses during hot screw rolling on pre-aged ZM61 magnesium alloys

摘要

In order to investigate the microstructure and texture evolution induced by precipitation during severe plastic deformation (SPD), pre-aging was conducted on ZM61 alloys, followed by screw rolling (at 300 °C), a special type of SPD technology. The mechanical properties were measured by uniaxial tensile testing at room temperature. The results showed that a gradient structure was obtained, and the grain size was more refined in the outer region along the radial direction. All samples expressed a basal texture, and the intensity gradually weakened when the pre-aging time increased, with the strength and ductility improving concurrently. The fracture elongation improved from 15.2% on as-received samples to 27.8% after pre-aging for 12 h, an 82.9% increase. This is mainly related to dynamic recrystallization mechanisms, including continuous dynamic recrystallization (CDRX), discontinuous dynamic recrystallization (DDRX), and particle simulated nucleation (PSN).