High-temperature chromium diffusion in austenitic stainless steel: Ab initio molecular dynamics simulations

Journal Article · 16 December 2023 · Chemical Physics Letters

DOI: https://doi.org/10.1016/j.cplett.2023.141036 · OSTI ID:2311263

Weck, Philippe F.  ^[1]; Kim, Eunja  ^[2]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2. Univ. of Texas at El Paso, TX (United States)

Chromium self-diffusion through stainless steel (SS) matrix and along grain boundaries is an important mechanism controlling SS structural materials corrosion. For this work, Cr diffusion in austenitic SS was simulated using canonical ab initio molecular dynamics with realistic models of type-316 SS bulk, with and without Cr vacancies, and a low-energy Σ3 twin boundary typically observed at active corrosion sites. Cr self-diffusion coefficients at 750 and 850 °C calculated using Einstein’s diffusion equation are 4.2 × 10^–6 and 8.1 × 10^–6 Ų ps^–1 in pristine bulk, 3.8 × 10^–3 and 5.5 × 10^–3 Ų ps^–1 in bulk including Cr vacancies, and 9.5 × 10^–2 and 1.0 × 10^–1 Ų ps^–1 at a Σ3[1 1 1]60° twin boundary.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Nuclear Energy (NE)
• Grant/Contract Number: NA0003525
• OSTI ID: 2311263
• Alternate ID(s): OSTI ID: 2246968
• Report Number(s): SAND--2024-00751J
• Journal Information: Chemical Physics Letters, Journal Name: Chemical Physics Letters Journal Issue: 1 Vol. 836; ISSN 0009-2614
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English