| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Computation Assisted Materials Development for Improved Corrosion Resistance
|
| Presentation Title |
The Effect of Solute Capture on Chlorine Chemisorption |
| Author(s) |
John Cavin, James M. Rondinelli |
| On-Site Speaker (Planned) |
John Cavin |
| Abstract Scope |
Attack from aqueous Cl- can threaten the stability of passivating oxides through several mechanisms including by facilitating the runaway growth of physical perturbations and by causing morphological instabilities through the electromechanical coupling of local electric fields. Here, we present our first principles work on the corrosion resistance of non-equilibrium oxides in the context of Cl- chemisorption, where non-equilibrium oxides are formed on alloy surfaces from solute capture. This mechanism allows cation compositions in the oxide to exceed their nominal equilibrium solubility limits. Using Ni-Cr alloys as a use case, we perform density functional theory calculations to show that rock salt (111) NiO surfaces with Cr replacing Ni in the first metal sublayer resists Cl- chemisorption better than pure NiO and pure Cr2O3. We also present results involving non-equilibrium oxides comprising Mo and W in NiO as well as corundum Cr2O3 with captured Ni to formulate structure-composition and chloride-resistance principles. |