Heterogeneous nucleation of α-Al primary crystal on L12 modified Al2.7Ni0.3Ti phase

The heterogeneous nucleation of α-Al primary crystal on the L12 modified Al2.7Ni0.3Ti (Al67Ni8Ti25) phase was investigated. To study the effectiveness of heterogeneous nucleation by the L12 modified Al2.7Ni0.3Ti phase, an Al-10 vol % Al2.7Ni0.3Ti refiner was fabricated by spark plasma sintering (SPS). It was found that the maximum grain refinement performance can be achieved by the Al-10 vol % Al2.7Ni0.3Ti refiner after a holding time of 690 s. The mechanical properties of pure Al casts were improved by using the Al-10 vol % Al2.7Ni0.3Ti refiner through grain refinement. However, the grain refinement performance is relatively weaker than expected. This is because the Al-10 vol % Al2.7Ni0.3Ti refiner does not have a high thermal stability.