Internal cooling process to prepare aluminium rheocasting feedstock

Immersion cooling and stirring are two elements of the internal cooling process recently proposed to produce aluminium rheocasting feedstock. They were employed in various combinations to identify the impact of each on the evolution of globular structures. AlSiMg melt sample water quenched above the liquidus point and after cooling into the semisolid temperature range produces predominantly dendritic dendritic features, typical of conventionally cast structures. Improvement in slurry features is noted when cooling below the liquidus temperature involves either stirring or immersion cooling. Internal cooling process which employs both immersion cooling and stirring produces smaller globules than those possible with stirring alone. Globular structures are obtained earlier and are refined further when internal cooling is extended to achieve higher solid fractions before quenching.