Ab Initio Molecular Dynamics Insights into Stress Corrosion Cracking and Dissolution of Metal Oxides.

ABSTRACT: Oxide phases such as α-Fe₂O₃ (hematite) and α-Al₂O₃ (corundum) are highly insoluble in water; however, subcritical crack growth has been observed in humidity nonetheless. Chemically induced bond breaking at the crack tip appears unlikely due to sterically hindered molecular transport. The molecular mechanics of a crack in corundum with a reactive force field reveal minimal lattice trapping, leading to bond breaking before sufficient space opens for water transport. To address this, we model a pre-built blunt crack with space for H₂O molecule adsorption at the tip and show that it reduces fracture toughness by lowering the critical J-integral. Then, we explore stress-enhanced dissolution to understand the mechanism of crack tip b

SUBMITTER: Felix LC 

PROVIDER: S-EPMC11818312 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature