I have taken on the task of simulating the impact on Ni-Al liquid metal droplets on a titanium surface using MD. I have experience with other MD codes, but very little with LAMMPS. I have a number of questions that members of this list can perhaps help with.
1. It seems from reading relevant literature that the standard potential functions used in liquid metal deposition simulations are based on EAM or FS+ potential functions. Can anyone point me to appropriate potential data for the Ni-Al system? What 'mixing' strategies are used for the force fields when 3 or more species (e.g. Ni+Al, Ti surface) are present?
2. What happens in the case of non-stoichiometric alloys (e.g. Ni + 5%wt Al)? Is there a recommended procedure for generation of such 'alchemical' potentials if I am not interested in distinguishing between the elements?
3. What is the recommended equilibration protocol for a liquid metal droplet using LAMMPS?
4. Is there any support within LAMMPS for defining, for a droplet impacting on a surface, a 'crash' region within the substrate in which the full potential expression is used, surrounded by a larger substrate region in which the atoms are constrained to only small deviations from their regular lattice positions, the interface between the two regions being handled with some kind of damping term (the goal being to reduce the effects of reflected impact pressure waves) ?
5. Can such simulations be 'coarse-grained' within LAMMPS to larger particles of the 'granular' type?
I would be very glad to get advice on any of these questions, pointers to literature or contact email addresses to groups doing similar research studies.
Many thanks in advance,