Modification of cast structure in Al-8 center dot 3Fe-0 center dot 8V-0 center dot 9Si alloy by magnesium treatment

Chill cast Al-8.3Fe-0.8V-0.9Si alloy shows massive precipitate particles of various morphologies, The morphology, size, and distribution of those precipitates can be considerably modified by Mg treatment. A residual Mg level of about 0.2 wt-% is required for effective modification. Magnesium can be conveniently introduced into a superheated Al-Fe-V-Si alloy melt as either Al-20Mg or Ni-20Mg master alloy. Analysis by EDX of the complex aluminide and silicide precipitates have confirmed that Mg and Ni enter into the lattice of such precipitates.