Numerical simulation for microstructure evolution in AM50 Mg alloy during hot rolling

The microstructure simulation of AM50 alloy rolled at different temperatures and roller speeds was investigated using a FEM software DEFORM-3D. Constitutive equations and dynamic recrystallization model used in DEFORM were developed based on the tension and compression tests at high temperature. The simulated results show that the inhomogeneous distribution of strain leads to a non-uniform recrystallized microstructure. Decreasing sheet temperature or increasing roller speed would help to refine recrystallized grains. The sheet temperature has a more significant effect on recrystallized fraction than roller speed. The hot rolling at a high temperature with a rapid roller speed is recommended for the manufacture of AM50 alloy sheet, expecting to achieve a homogeneous microstructure with moderate recrystallized grain size.