Influence of nitrogen on the synthesis and nucleation ability of TiCx in Al–Ti–C master alloy

Abstract In this study, a group of Al–Ti–C master alloy has been prepared in an atmosphere with different concentration of N2. The master alloys are analyzed by field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). It is discovered that N atoms can be doped into TiCx at a certain concentration of N2 while it will form AlN if the concentration is higher. Adding Al–Ti–C master alloy with N doped TiCx particles in molten aluminum, the average grain size of α-Al can be reduced from 3320 μm to 189 μm and the efficiency does not fade within 60 min. It is supposed that the grain refinement efficiency and stability of TiCx is improved obviously after N doping. This master alloy exhibits potential to promote the application of grain refiner in industries.