The stress-strain curves of AZ31 magnesium alloy were mapped by the Gleeble-1500D hot simulator. ECAE process for AZ31 magnesium alloy was simulated by the DEFORMA-3D software to understand effects of different internal fillet radiuses on stress and strain. The results reveal that with increasing in the internal fillet radius

the surface of the sample becomes smooth

and average stress in internal fillet is decreased with average equivalent strain increase

while the middle steady deformation zone becomes smaller.