ONR MURI: Understanding Corrosion in 4D
Corrosion of metals is a ubiquitous phenomenon that costs the US economy hundreds of billions of dollars each year. As such, it is important to understand how various alloys oxidize and corrode so that new corrosion resistant alloys can be designed. The goal of the Office of Naval Research MURI: Understanding Corrosion in 4D is to use a combination of experiment, computation, and theory to form a detailed understanding of the early stages of oxidation and corrosion. The project is a collaboration between Northwestern University, the University of Wisconsin-Madison, and the University of Virginia.
As part of this ONR MURI, the Voorhees group is engaged in the development of simulations and theory for the early stages of oxidation of Ni-Cr-Al alloys. We have developed a phase-field model for metal oxidation, and a mean-field model of oxide island growth. Recently, the MURI team has identified solute trapping and morphological instabilities as important phenomena in oxide growth. We have developed a thermodynamic and kinetic model for solute trapping in oxides, focusing on the Ni-Cr alloy system. Morphological instabilities in oxide growth are being studied using linear perturbation theory and stability analyses, as well as phase-field modeling.
More information about this project can be found here
Participants
- Quentin Sherman (alum)
- Kyoungdoc Kim (alum)
- Rohit Ramanathan (alum)
Publications
Names in bold are Voorhees Research Group members.
K. Kim, Q.C. Sherman, L.K. Aagesen, P.W. Voorhees, “Phase-field Model of Oxidation: Kinetics,” Physical Review E, 101 (2020).
R. Ramanathan, P. W. Voorhees, “Morphological Stability of Steady-State Passive Oxide Films,” Electrochimica Acta (2019).
X. X. Yu, A. Gulec, Q. Sherman, K. L. Cwalina, J. R. Scully, J. H. Perepezko, P. W. Voorhees, L. D. Marks, “Nonequilibrium Solute Capture in Passivating Oxide Films,” Physical Review Letters, 121 (2018)
R. Ramanathan, G. Ramalingam, J. H. Perepezko, P. Reinke, P. W. Voorhees, “Evolution of NiO Island Size Distributions During the Oxidation of a Ni-5Cr Alloy: Experiment and Modelling,” ACS Applied Material Interfaces, 10 (2018)
X. X. Yu, A. Gulec, A. Yoon, J. M. Zuo, P. W. Voorhees, L. D. Marks, “Direct Observation of ‘Pac-Man’ Coarsening,” Nano Letters, 17 (2017)
Q. C. Sherman, P. W. Voorhees, “Phase-field Model of Oxidation: Equilibrium,” Physical Review E, 95 (2017).
Space-charge effects during oxidation
1D phase-field results for the equilibrium between the oxide film and a pure metal. Left shows the results for an oxide film that is much thicker than the Debye length of the film, when the film is nominally charge neutral. The right shows the results for a film that is as thick as the Debye length, and shows the development of a space charge in the film.
Modeling oxide growth
Modeling growth and coalescence of NiO islands during oxidation of a Ni-5Cr alloy. Left shows an STM micrograph of the alloy surface decorated with oxide islands. Right shows model results for the size distribution evolution using several different diffusion screening lengths.