Influence of Sc modification on the fluidity of an A356 aluminum alloy

Influence of Sc modification on the fluidity of an A356 aluminum alloy was investigated. To use Sc as a practical and effective eutectic Si modifier, it is crucial to understand the effects of Sc on castability, including fluidity. Higher fluidity can reduce the temperature needed to fill a mold. The fluidity increased with higher mean shape factor, which was from the effect of Sc modification. This increase of fluidity was evident at all tested temperatures, especially within the higher temperature range of 690-720 degrees C. We found that Sc also effectively refined the grain size. The fluidity of these reduced grain size samples is higher than that of non-grain refined samples. However, the sample with the finest grain size, 0.4wt.% Sc, did not have better fluidity than samples with less grain refined grains (0.2wt.% Sc and 0.2wt.% Sc + 0.2 wt.% Zr). (C) 2009 Published by Elsevier B.V.