The 7075 aluminum alloy semi-solid slurry was prepared by ICSPC（inverted cone-shaped pouring channel process）process

combined with temperature homogenization（TH）treatment to make the slurry uniform and to control solid fraction suitable for the follow-up rheocasting.Influence of processing parameters on the microstructure evolution of primaryα-Al during TH treatment was investigated. The results show that the TH treatment can reduce the difference of temperature between the center and the edge in the slurry to meet the rheocasting

meanwhile

microstructure in the semi-solid slurry after TH treatment is spheroidized increasingly.With the heating power in range of 2.0

6

.4kW

as the power increases

the time of TH treatment is decreased

and the size of the primaryα-Al is refined with a slightly decrease of shape factor.However

when the heating power is 10.0kW

as a result of phenomenon of alloy re-melting dramatically and severely coalescence of the grain

spheroidization of the grain in the semi-solid slurry is deteriorated sharply.At a given heating power

as the slurry temperature dropped in range of 628

6

32℃

the size of the primaryα-Al is refined increasingly

and finally a high-quality semi-solid slurry appears.