Project title: Interfacial free energies in pure metal and alloy melts 

Supervisors: Prof Michael Finnis, Prof Alessandro De Vita and Prof Peter Lee

Project description:

The aim of my project is to calculate the interfacial free energies in pure metal and alloy melts using a metadynamics approach based on the work of Angioletti-Uberti et al. [1].  Interfacial energetics can be difficult to deduce and measure experimentally and so simulation plays its part by providing another means of getting an answer.  Interfacial energetics is not merely of theoretical interest but influences the resulting microstructure of a material which in turn affects its mechanical properties among other things. 

This project is intrinsically multiscale.  Firstly, the formulation of interatomic potentials capable of representing the interaction between atoms in multicomponent solid and liquid phases is explored.  This is a bridging of quantum mechanical accuracy into an atomistic regime.  The calculation of interfacial free energy with the metadynamic approach of [1] bridges time scales from picoseconds to nanoseconds.  It is envisaged that the thermodynamic information outputted from the metadynamic simulations will be fed into a mesoscale model (for example, phase-field) to simulate the solidification microstructures.  The project thus spans the length-scale from the electronic to the mesoscale and picosecond to the nanosecond time scale.

[1]  Solid-liquid interface free energy through metadynamics simulations, Angioletti-Uberti, Stefano and Ceriotti, Michele and Lee, Peter D. and Finnis, Mike W., Phys. Rev. B, 2010, 81,125416