Could you tell me how to get the pair_coeff parameters of the non-bonded interactions between aluminum and polyurea please? I couldn't find them in the interface force field. Or do I need calculate them by myself? Thank you very much.

Huang Xiaona Yes, those have to be calculated using an appropriate mixing rule. I have used the sixthpower mixing rule. Information about the mixing rules can be found here: https://lammps.sandia.gov/doc/pair_modify.html

Thank you for your reply. I consulted the author of the interface force field a few questions. The email contents are attached. I think maybe we can describe polymer and metal only with the interface force field.

We modeled the shock response of polymer-metal multilayers and found that EAM accurately reproduces the experimental shock Hugoniot of the metal. Here is one of our publications, where we have used the LAMMPS input files given above, and it explains how we modeled nonbonded interactions: Article Molecular dynamics study of the mechanical behaviour of ultr...

Thank you for your reply so much.

Here is another related publication, where we simulated impact tests of aluminum-polyurea multilayers to find their ballistic limit velocities: Preprint Superior Dynamic Penetration Resistance of Nanoscale Multila...

Hello Nuwan,

Thank you so much for sharing, could you share the input files for LAMMPS for the to model Aluminum-polyurea interface?

Thanks,

Hello Carlos Gamez,

The required LAMMPS input files are available at the bottom of the original discussion. More information about the simulation is available here: https://github.com/nuwan-d/polymer_metal_interface

Hello Nuwan Dewapriya ,

Yes, that github page is really helpful, but the polymer described in the files is polyurethane, not polyurea. I think you used polyurethane for the first paper and polyurea for the second paper you mentioned.

Actually, the first files you posted helped me to get started with my project, so I really appreciate the fact you are sharing them.

Thanks, Carlos Gamez. Yes, the files are for polyurethane. Actually, we are still continuing our work on polyurethane and couldn't publish a paper based on that work yet.