Effect of twinning on flow stress during initial stage of hot compression of twin roll cast Mg-5.51Zn-0.49Zr alloy

Abstract

A Thermecmastor-Z hot deformation simulator, optical microscopy, XRD and TEM were employed to characterize the flow stress behavior and microstructure of twin roll cast ZK60 magnesium alloy during initial stage of hot compression at elevated temperature of 300 °C and 400 °C and a given strain rate of 10⁻² s⁻¹. The results suggest that flow stress drop during initial stage of hot compression at 300°C, generally led by dynamic recrystallization, is attributed to twinning, correspondingly to dynamic recrystallization as deformation temperature is raised to 400 °C.

Keywords

magnesium alloy / basal slip / non-basal slip / twinning / hot deformation / recrystallization

References

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