Semisolid microstructure of Mg2Si/Al composite by cooling slope cast and its evolution during partial remelting process

An in situ Mg2Si/Al–Si–Cu composite with semisolid structure was fabricated by cooling slope cast and partial remelting process. The as-cast microstructure, and effect of isothermal holding time on the morphology, size and shape factor of the grains were investigated. The results show that the morphology of primary Mg2Si and α-Al grains in the composite are globular and/or elliptic after partial remelting process. The size and shape factor of α-Al grains increase with the isothermal holding time.