| The semisolid aluminum alloy slurry has been prepared by the Low Superheat Pouring Process with Shearing Field technology (LSPSF process), which include the proper rotating speed and heat exchange condition barrel. In order to investigate how the pouring condition (pouring temperature) and barrel heat exchange condition (inclined degree, rotate speed, preheat temperature) affect the microstructure of semisolid slurry, the orthogonal experiment have been used to examine the temperature at the outlet of barrel and the microstructure of semisolid slurry.The experiment results show that the pouring condition and heat exchange of barrel affect the grain structure and dimension evidently. Proper low pouring temperature can fabricate near-round grains, or, the high pouring temperature make the coarse dendrite grains because many nuclei remelt and can't survive at the outlet of barrel. When the pouring temperature is about 50 ℃ higher than the liquidus, the perfect semisolid slurry can be prepared at the scope of 20 ℃. So, the LSPSF process can be manipulated conveniently and popularized.The distributing of melt temperature in the rotational barrel is influenced by the interaction of pouring temperature and shear field of barrel, then the effective nucleation rate changes consequently, and the structure and dimension of primary particles change finally. None but matched pouring temperature and rotating speed of barrel can increased effective nucleation rate and obtain high quality semisolid slurry. Besides, the inclined degree and dimension of the barrel, and the pouring flux of melt are also the vital parameters in this semisolid slurry making process.The power-law model is used to describe the rheological speciality in the platform of ProCASTTMsoftware and Finite difference method (AnyCastingTM. The flow and temperature distribution of A3 56 alloy in the barrel by the LSPSF process were investigated in different pouring temperature and heat exchange condition.
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