The effects of parameters of a novel internal cooling thermal equilibrium (ICTE) process on microstructure evolution in semi-solid A356 aluminium alloys were investigated. The results indicated that a low predetermined temperature ( T P), a higher mechanical stirring intensity for the thermal equilibrium body (TEB) and a reduced melt mass contributed to obtaining fine grained semi-solid structures. The cooling effect of TEB combined with dendritic remelting fractures of solidified shells formed on surface of TEB at room temperature promoted massive nucleation in alloy melt and contributed to obtaining numerous fine primary solid phases. The ICTE process, which regulated stirring time of TEB, obtained numerous spherical grains and simplified the operational process.

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