The effect of deformation degree on deformation microstructure in the preparation of semi-solid AZ91D alloy
billet by Strain Induced Melt Activated (SIMA) process was studied and the relationship between deformation degree and
eutectic melting activation energy was studied by Differential Scanning Calorimetry (DSC). The results showed that with
an increase in deformation degree, the original microstructure of the alloy changed from dendrites to fragmentary grains
where there were twins and dislocations. When the deformation degree was 40%, the decreased amount of eutectic melting
activation energy was not significant. Melting point of eutectic decreased slightly with increasing deformation degree.