Supplementary Material to "Unravelling densification during sintering by multiscale modelling of grain motion"

Supplementary material to the paper "Unravelling densification during sintering by multiscale modelling of grain motion" ( formerly named "Investigating densification during sintering with molecular dynamics and phase-field simulations") by Marco Seiz, Henrik Hierl, Britta Nestler. This contains videos of simulation data as well as a simple python implementation for the rigid-body motion model determined within the paper. The initial particle packings employed in the paper are also contained for this, along with a simple reader for usage in the python implementation. Finally, some more detailed analysis of the raw data concerning the coordination number is presented.

A binder for quick trialling is available at

https://mybinder.org/v2/gh/https%3A%2F%2Fgit.scc.kit.edu%2Fxt5201%2Fsupmat-densification-md-pf/HEAD

with the base repository being located at

https://git.scc.kit.edu/xt5201/supmat-densification-md-pf/-/tree/master/ .

{advmu,md}_blocks.webm: A simulation of 16 grains in a chain calculated with both model ADV-mu and the MD-inspired (MDi) model developed in the paper. Yellow indicates the solid grains, dark indigo the vapour, red lines any interfaces. Model ADV-mu eliminates the pores in a step-wise manner from the outside in, suggesting inhomogeneous densification. Model MDi eliminates them almost at the same time, suggesting homogeneous densification.

full.webm: A simulation in a 400^3 voxel simulation box with particles of initial size R=12 cells = 12nm. The mesh visualized here is based on the largest local phase-field excepting the vapour phase-field. This allows introducing an etching-like effect with an appropriate choice of contour level l, with l=0.6 employed here to show grain boundaries and higher order junctions. Macroscopic densification is quite evident here. Note that the early part of the simulation was written out at a higher frequency, so there's an apparent jump in densification rate; it actually decreases monotonically.

fracture.webm: Same data as above, but after "fracturing" along a (011) plane. This allows the inner part of the green body to be visualized, showing the polyhedralization of the grain structure.

contact-solver.ipynb: Shows how to use the python implementation of the rigid-body motion model solver coded in helpers.py.

packs.zip: packs/*dat: The initial position and sizes (uniform) of the particles, can be used as input for the above.

coordination-extras.ipynb: Analysis of the raw data of the contact detection for a simulation.

data.zip: data/* : Data used in the above notebook.