Simulation of Si3N4

Dear LAMMPS users,

I’m trying to simulate mechanical behavior of Beta silicon nitride thin layer in z direction. To gain that, I used the attached input files and I get the attached curve as stress -strain curve. However, the curve shouldn’t be correct as Si3N4 is a brittle material and based on the literature we expect it to fail within 5% of strain and a stress below 20 GPa. So, I tried several possibilities. But, I couldn’t solve the issue. Therefore, I wonder if you could please help me out.

Sincerely,

Ali

Stress - Strain.PNG

Dear LAMMPS users,

I'm trying to simulate mechanical behavior of Beta silicon nitride thin
layer in z direction. To gain that, I used the attached input files and I
get the attached curve as stress -strain curve. However, the curve
shouldn't be correct as Si3N4 is a brittle material and based on the
literature we expect it to fail within 5% of strain and a stress below 20
GPa. So, I tried several possibilities. But, I couldn't solve the issue.
Therefore, I wonder if you could please help me out.

​help you how?
you don't provide any tangible information to assess where any potential
problems could be. there could be issues with the force field, issues with
the geometry, issues with the workflow, issues with the choice of
parameters, issues with the units, issues how you compute properties and so
on.​

thus one would need a well functioning crystal ball to provide meaningful
help.
i've tried several times to request one from [email protected], but
apparently i seem to be stuck on the "naughty" list.
perhaps you can put in a good word for me.

axel.