The Effect of Spin Casting Process Parameters on Shrinkage in Zinc Alloy

Shrinkage causes a change in dimension of metal castings from an original design. The metalcasting shrinkage depends on varied parameters, and hence makes problems in industrial casting manufacture.The objective of this work is to study the effect of spin casting process parameters on shrinkage ofZn-4.0Al-3.1Cu-0.5Mg alloy. Casting temperatures in the range of 420-480 °C, rotation speeds of 300-500rpm and various gate and runner sizes were studied. Moulds were made of high temperature resistant siliconerubber. The results show that the lowest volume shrinkage 3.92 ± 0.56% occurs at the casting temperatureof 420 °C and the rotational speed of 500 rpm. The shrinkage of sample sections parallel to the spin castdirection is lower than those of perpendicular to the spin cast direction. The increase in runner length resultsin the lower shrinkage, while the increase in runner size does not affect the shrinkage of samples. It couldbe concluded that higher casting temperatures result in higher shrinkage. On the other hand, the increaseof spin speed results in the reduction of shrinkage. So, conclusions of this work would be useful guidanceof mould design for spin casting industrial. Keywords : Casting Sample / Shrinkage / Spin Casting / Zinc Alloy