Effect of Adding Lanthanum to Al – 5% Ti – 1% B Master Alloy on the Efficiency of Grain Refinement in Aluminum and Al – 7% Si Alloy

An Al – 5% Ti – 1% B master alloy with a lanthanum addition is prepared by improved technology employing halides. The effect of adding lanthanum to master alloy, introduced into melts of pure aluminum and of Al – 7% Si alloy, on the microstructure and degree of casting grain refinement is established. Asignificant modifying effect of adding lanthanum to Al – 5% Ti – 1% B master alloy during treatment of pure aluminum and its weak effect on modifying Al – 7% Si alloy are established.