Gerald T.

PhD (Metallurgy and Materials Engineering)

Master of Technology (Materials Science and Engineering)

Bachelor of Engineering (Mechanical)

Thixocasting requires manufacturing of billets with non-dendritic microstructure. Aluminum alloy A356 billets were produced by rheocasting in a mould placed inside a linear electromagnetic stirrer. Subsequent heat treatment was used to produce a transition from rosette to globular microstructure. The current and the duration of stirring were explored as control parameters. Simultaneous induction heating of the billet during stirring was quantified using experimentally determined thermal profiles. The effect

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

Phase-field method uses a non-conserved order parameter to define the phase state of a system and is a versatile method for moving boundary problems. It is a method of choice for simulating microstructure evolution in the domain of materials engineering. Solution of phase-field evolution equations avoids explicit tracking of interfaces and is often implemented on a structured grid to capture microstructure evolution in a simple and elegant manner. Restrictions on the grid size to accurately capture the inte