Computational modelling of dendritic to globular transition using an isothermal binary phase-field model

摘要

Globular microstructure is suitable for high pressure die casting of semi-solid billets. This is achieved by means of mechanical deformation of the melt or by means of a forced convection in the presence of a thermal gradient. The morphological evolution in an alloy with the starting microstructure as predominantly dendritic is simulated using the phase-field technique. An attempt is made to study the effect of varied thermal profiles that are imposed on the solidified dendrite and the morphological changes effected there upon. Two dimensional simulations are performed for a dilute alloy of a simple lens type phase diagram and the results are presented.