Building a Fe-Cr Lattice Input

Hi.

Looking to build an Iron Chromium stainless steel and am curious about the best way to set up an input file. I know how to build a simulation box for a metal lattice, but what about when there are two types of metals in the lattice. For example, if I only wanted 10% chromium. I know I need to have 2 types of atoms, but is there a way to specify a concentration of each? Can this be done in the setting up of the simulation or should I use something like atomsk.

Thanks!

Hi.

Looking to build an Iron Chromium stainless steel and am curious about the
best way to set up an input file. I know how to build a simulation box for
a metal lattice, but what about when there are two types of metals in the
lattice. For example, if I only wanted 10% chromium. I know I need to have
2 types of atoms, but is there a way to specify a concentration of each?
Can this be done in the setting up of the simulation or should I use
something like atomsk.

‚Äčeither is possible. for a small concentration of the second element, it is
usually sufficient to set up a system of the major component, but reserve
space for two atom types, equilibrate it‚Äč, and then using the set command
with the type/fraction option to change a given percentage of the atoms to
the second element and then continue equilibration and finally run
production.

axel.

Thanks for the response. This makes sense to me and appears to be working.

So would you run two equilibrations? Right now without the chromium I minimize my structure, then equilibrate it at a certain temperature, and then start applying strain.

In the case of adding chromium I am minimizing, equilibrating at a certain temperature, changing a percentage to chromium, then minimizing again. Should I replace that last minimization with an equilibration?

Thanks

Liam

Thanks for the response. This makes sense to me and appears to be working.

So would you run two equilibrations? Right now without the chromium I
minimize my structure, then equilibrate it at a certain temperature, and
then start applying strain.

In the case of adding chromium I am minimizing, equilibrating at a certain
temperature, changing a percentage to chromium, then minimizing again.
Should I replace that last minimization with an equilibration?

to have a comparable protocol, you should create the alloyed compound
directly (create_atoms and set type) and then follow the same
procedure as with the pure compound.
since you are replacing random atoms, you should do multiple runs with
different random number seeds to have a measure for what the average
result is and how much it spreads.

axel.

Ok great. I did this and used OVITO as well and the values I am getting are expected based on literature.

Thanks

Liam