Atomistic Simulations of Early-Stage Oxidation Mechanisms in Oxide Dispersion Strengthened Alloys

Recent innovations in additive manufacturing technologies at NASA have enabled the development of new oxide dispersion strengthened (ODS) alloys which exhibit remarkable improvements to high temperature properties including creep and oxidation resistance. The mechanistic origins of these excellent properties are unclear, and it is likely that they can be further optimized. Here we present the development of several new atomistic simulation tools, implemented in the open-source LAMMPS software, which allow for large-scale molecular dynamics simulations of metal/oxide systems. We apply these techniques to study the early-stage oxidation mechanisms in Ni, achieving results consistent with experiments at lower temperatures and revealing a new mechanism at elevated temperatures. We also discuss preliminary results for oxidation in the Ni-Y2O3 system, comparing mechanisms to pure Ni and providing possible reasons for the improved oxidation resistance observed in ODS alloys.