Fabrication of a New Al-Ti-C Master Alloy and its Refining Effect on AZ31

Abstract

The Al-Ti-C master alloy with excessive carbon content was prepared by the self-propagating high-temperature synthesis (SHS) in melt method. The master alloy mainly contains Al4C3 and TiC phases, which exhibits satisfactory refining effect on AZ31 alloy. With 1.5wt.% addition of the master alloy, the grain size reduced from 280 μm to 109 μm. The tensile properties are also improved with the refinement of grain structure. The ultimate tensile strength increased from 105 MPa to 156 MPa while the elongation increased from 8.4% to 13.6%. The Al4C3 particles and TiC particles play important role in the refining process due to their low disregistry with α-Mg grains.