Predicting carbon diffusion in cementite from first principles

Combining first-principles calculations with recently developed statistical physics tools, we determine carbon diffusion mechanisms and the resulting coefficients in pure-Fe weakly alloyed ${M}_{3}\mathrm{C}$ cementites. The predicted ${\mathrm{Fe}}_{3}\mathrm{C}$ are good agreement experimental measurements of carburization rate ferritic steels. In our proposed mechanisms, C migrates by jumps between interstitial sites rather than via Frenkel pair mechanism, as previous studies based on semiempirical simulations. cementites, can be slowed down due to presence Mn solutes up 500 K, while it is mostly unaffected addition Mo or Cr solutes.