Effects of combinative addition of lanthanum and boron on grain refinement of Al-Si casting alloys

In this paper, with the combinative addition of La and B elements, the grain refinement of Al-Si alloys with different contents of Si was achieved. Compared to individual addition of B element, the combinative addition of La and B elements can effectively refine the grains of Al-Si alloys. The addition of La element suppresses the mutual poisoning between Sr and B elements, benefiting the formation of a fully modified eutectic silicon structure in the Al-Si alloys. This work also indicates that the tensile properties, especially the elongation, of Al-Si alloys are enhanced with the addition of La element. (C) 2014 Elsevier Ltd. All rights reserved.