Cold-spray aluminum MD on a cloud LAMMPS runner

Cold spray deposits metal particles onto a substrate at high velocity without melting the bulk. At the atomistic scale that is an impact problem: an embedded-atom potential, optional electrostatic drive, and dumps of stress during approach, impact, and relax.

Source calculation

The Computational Materials Research Group published an open LAMMPS script for multi-particle electrostatic cold spray of aluminum with an EAM/alloy potential:

GitHub repository
Mishra, A. (2026). Molecular Dynamics Simulation of Multi-Particle Electrostatic Cold Spray Deposition of Aluminum Using EAM Potential. Zenodo. https://doi.org/10.5281/zenodo.20061969
Original work licensed CC BY-NC 4.0 (attribution; non-commercial).

Their setup is fully atomistic: an FCC Al substrate, two spherical nanoparticles, per-atom charges, a uniform electric field (fix efield), NVE particles / NVT substrate, and per-atom von Mises stress in the dumps. EAM (embedded-atom method) is a many-body potential used for metals; the file Al99.eam.alloy must sit next to the input because pair_coeff names it.

Methods (this run)

An educational-scale version was submitted from app.quickmdsim.com and executed with LAMMPS in a cloud container on one CPU core (23 s wall time).

994 atoms of FCC aluminum (EAM/alloy, Al99.eam.alloy)
272 of those atoms in the two nanoparticles
Droplets reach the slab at ~2.4 ps and deform into it
Phase dumps: approach, high-frequency impact, relax, with von Mises and pressure

Side view of two aluminum nanoparticles hitting an Al substrate, atoms colored by von Mises stress — Mid-impact still. Side view; droplets colored by von Mises stress.

Approach, impact, relax from the same dumps. Fixed camera.

What the runner has to support

Materials jobs are almost never a single file. QuickMDSim copies every project file into the working directory, so pair_coeff * * Al99.eam.alloy Al resolves. The container accepts the job immediately and runs LAMMPS in the background; credits decrement from measured vCPU-seconds when the run finishes.

Files

Repo path demos/cold-spray-al/: input.lammps, Al99.eam.alloy, README.md. Regions use units box so Angstrom sizes stay Angstroms after lattice fcc. Sized for the free tier; enlarge the box for research geometries.

Open app.quickmdsim.com and create a project
Add input.lammps as the primary file and Al99.eam.alloy beside it
Run. Download dump.impact.lammpstrj and color by v_von_mises in OVITO

Physics idea and analysis structure follow Mishra (2026). Cite the Zenodo record and respect CC BY-NC 4.0 if you use their geometry in research.