The solution
treatment conditions depend on the casting method, in order to
produce a nearly homogeneous solid solution. Shivkumar [8]
showed that, for permanent mould cast test bars of A356 alloy, a
solution heat treatment of only 50 min at 540 1C was sufficient to
obtain a homogeneous distribution of silicon and magnesium in
the α aluminium dendrites. Zhang [9] studied the possibility of
using 30 min of solution treatment at 540 1C with A356 cast by
low pressure die casting. Compared with the conventional casting
methods, in the SSM processes the alloy remains in semisolid
temperature for a significant period of time, and the cooling rate is
faster than high pressure die casting (HPDC). Accordingly, the
structure of these components is more homogeneous, and the
inter-metallic compounds, which are located next to the eutectic
microconstituent, surrounding α-phase globules, shows a smaller
size. These circumstances can significantly reduce the solution
time of the T6 heat treatment, when they are applied to components
manufactured in semisolid state.