Effects of electric pulse on the solidified structure of Al-22%Si alloy

The effects of electric pulse on the solidified structure of Al-22%Si alloy was investigated by means of metalloscope and DSC.The results show that the electric pulse with proper parameters can refine the grain of the solidified structrue of samples markedly,and the size of primary silicon decreases.Besides,DSC curves show that the freezing-point of primary phase decreases from 736.94℃ to 720.16℃ and the freezing latent heat decreases 4.1J/kg.Theoretical analysis shows that the interaction between electric pulse and melt makes the size of silicon cluster in the melt smaller,therefore promotes the nucleation of the primary silicon.