THEORY OF OXYGEN TRACER DIFFUSION ALONG GRAIN-BOUNDARIES AND IN THE BULK IN 2-STAGE OXIDATION EXPERIMENTS .3. MONTE-CARLO SIMULATIONS

In Parts I and II of this work we developed a model of oxygen O-18 tra cer diffusion in a growing polycrystalline oxide film with parallel gr ain boundaries. In this paper we solve the basic equations of the mode l numerically using the Monte-Carlo approach. We introduce a new simul ation technique that takes into account the finite-size effect, the fi lm growth, the effect of the oxygen chemical potential gradient across the film, and other factors. We apply this technique for the simulati on of the most important cases encountered in two-stage oxidation expe riments. The oxygen tracer profiles obtained demonstrate good agreemen t with the previous theoretical analysis, the finite-difference soluti on of the problem, and exact analytical solutions when available. We d iscuss possible extensions of the simulation method to provide a more realistic description of the oxide growth.