This paper investigates the effect of vacancies on dislocation nucleation in iron by means of molecular dynamics atomistic simulations at low temperatures. Increasing the vacancy concentration resulted in a decrease in the load at the onset of plasticity following a power law relationship. Dislocations did not nucleate at a vacancy in these simulations. This suggests that vacancies, even without diffusing within the solid, may impact experimental observations of dislocation nucleation using nano-indentation.

Atomistic Simulations of Nanoindentation in the Presence of Vacancies. E.K.Njeim, D.F.Bahr: Scripta Materialia, 2010, 62[8], 598-601