The Influence of Gravity on the Composition of Directionally Solidified Al-In Hypermonotectic Binary Alloy

Recently, even though the conditions that produce fine composition structure of parallel lamellae or rods for the monotectic alloy during directional solidification have been examined, there are a little researches about the effects of gravity on the composition distribution of hypermonotectic alloys directionally solidified, particular in the route of sedimentation of the more dense of the two immiscible liquid phases directionally solidified AI-In hypermonotectic binary alloy. On the other hand, fluid flow resulted mainly from buoyancy and thermocapillary forces in solidifying hypermonotectic alloys are not completely understood. In this present paper, the route of sedimentation of the more dense of the two immiscible liquid phases directionally solidified Al-In hypermonotectic binary alloy is examined to better understand the mechanism of separation of the two immiscible liquid. In this article, in order to investigate the route of sedimentation of the more dense of the two immiscible liquid phases directionally solidified Al-In hypermonotectic binary alloy, upward directional solidification expriments have been carried out under the condition of Ig. The composition of directionally solidified Al-In hypermonotectic binary alloy has been measured with the increase of fraction solidified. Results show that the In zone formed at the bottom of a sample when the temperature gradient is the smaller. It was noted that the main route of sedimentation of the more sdense of the two immiscible liquid phases directionally solidified Al-In hypermonotectic binary alloy is the alloy-crucible combination.