The effects of the Ti:B ratio, the meit holding temperature and the melt mechanical agitation on the performance of aluminum
grain refinement master alloys were investigated using small ingot castings. The results confirm that the presence of dissolved Ti
in the melt is the key factor for effective grain refinement. omogenizing the distribution of heterogeneous nuclei in the melt by
mechanical agitation can further enhance the performance of Ti-B based master alloy. When the amount of disso!ved Ti in the
melt is less than the peritectic point, the columnar uiaxed transition in master alloy treated melt is more sensitive to heat
transfer variation rather than to the number of Ti particles retained in the melt. Slow cooling is recommended to avoid
columnar growth. As the holding temperature increases, inoculation fade occurs. 0 1937 EIsevier Scieace §.A.