Microstructure and Grain Refining Performance of a New Al-Ti-C Master Alloy (RESEARCH NOTE)

Control of microstructure parameters that affecting the Al-Ti-C master alloys grain refining efficiency is leading to improve the aluminum grain refinement. This study was an attempt to produce Al-Ti-C master alloys that provide these controlling factors with relying on the solute effect theory. The produced master alloys were examined by using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD); moreover, the effect of them on pure aluminum was investigated. Produced Al-6Ti-1C master alloy contained Ti and TiC particles within the aluminum matrix and Al-4Ti-1C contained TiC particles within the aluminum matrix. As the result, produced Al-6Ti-1C master alloy is a more efficient grain refiner for pure aluminum compared with the Al-4Ti-1C one that verified the effect of Ti particles for grain refinement. The results indicated Al-6Ti-1C master alloy had maximum grain refining performance when holding time was 2 minutes, temperature was 983 K, and master alloy addition level was 1% wt. Finally, a new Al-Ti-C master alloy with excellent refinement was prepared successfully.