A new nucleation mechanism of primary Si by like-peritectic coupling of AlP and Al4C3 in near eutectic Al–Si alloy

The effect of TiC particles on the phosphorous modification efficiency in near eutectic Al–Si alloy and a new nucleating mechanism was studied in this paper. The results show that the phosphorous modification efficiency can be significantly improved and the sizes of the primary Si can be obviously refined after the addition of trace TiC particles. EPMA shows there is a coupling of AlP and Al4C3 particles in the center of primary Si, and a new nucleation mechanism of primary Si by like-peritectic coupling of AlP and Al4C3 was presented. The formation mechanism of like-peritectic coupling of the particles was also discussed.