Revealing the roles of Al4C3 and Al8Mn5 during α-Mg nucleation in Mg-Al based alloys

After adding Al-3C master alloy, Al4C3 particle clusters are interspersed in the melts. For Mg-9Al, α-Mg directly nucleates on Al4C3. While for AZ91, Al8Mn5 precipitates before α-Mg and have a clustering relationship with Al4C3, and finally α-Mg nucleates on Al4C3.407