Semisolid A356 alloy feedstock poured through a serpentine channel

Fine spheroidal and equiaxed nondendritic microstructures required for semisolid casting can be formed through a serpen-tine pouring channel. Effects of the pouring temperature and the vertical section length of the serpentine pouring channel were stud-ied. The results indicate that both favorable semisolid microstructures of A356 aluminum alloy can be generated by a serpentine pouring channel, and the solid shell inside the channel can be avoided when the pouring temperature is in the range from 660 to 680℃. It is also shown that the vertical section length of the serpentine pouring channel has a significant influence on the micro-structure of the feedstock, namely both the microstructure of the feedstock and the microstructurc uniformity in the radial direction get worse when the vertical section length is shortened; moreover, the pouring temperature for obtaining the feedstock with suitable microstructure decreases. The relevant mechanisms were discussed.