<p>Effects of grain refinement using an Al–10Ti–5B master alloy on the hot tearing susceptibility of A206 alloy were examined. The results from real-time thermal and load analyses along with subsequent macroscopic and microscopic examinations of the castings were used to evaluate the predictions of three different hot tearing susceptibility models. Thermal analysis showed that grain refinement elevated the liquidus temperature and lowered the solidus temperature of the alloy with no significant impact on its coherency temperature. Davies's criterion suggested that, contrary to the experimental results, grain refinement would decrease hot tearing susceptibility of the alloy. NNC indicated that hot tearing susceptibility was reduced at a small grain refinement addition but increased at higher additions. Load rate criterion indicated that hot tearing susceptibility was increased with increasing grain refinement. Davies's criterion indicated that hot tearing susceptibility was increased at a low grain refinement addition but reduced at higher additions.</p>