Directional growth of Al-Mg2Si eutectic alloy in the SZ2 unmanned spaceship

This paper reports the investigation results on directional growth of Al−Mg2Si eutectic alloy in the SZ2 unmanned spaceship. The analysis shows that microgravity has influence on the directional growth of Al−Mg2Si eutectic alloy. The eutectic colony in space-grown sample is larger than that in ground-grown sample, and the directional effect is not so good as that of terrestrial sample. But there is no obvious difference in the lamellar thickness between these samples, and lamellar interspacing in space sample is smaller than that grown on the ground. A simple discussion is done on the gravity effect on the directional growth of Al−Mg2Si eutectic alloy.