Understanding slow-growing alumina scale mediated by reactive elements: Perspective via local metal-oxygen bonding strength

Journal Article · 20 March 2018 · Scripta Materialia

DOI: https://doi.org/10.1016/j.scriptamat.2018.03.002 · OSTI ID:1538803

Shang, Shun-Li ^[1]; Wang, Yi ^[2]; Gleeson, Brian ^[3]; Liu, Zi-Kui ^[2]

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1. Pennsylvania State University, University Park, PA (United States); DOE/OSTI
2. Pennsylvania State University, University Park, PA (United States)
3. University of Pittsburgh, PA (United States)

Interatomic bonding strength/energy can be quantified by stretching force constants (SFC) after first-principles phonon calculations. In this report we show that the slow-growing alumina (α-Al₂O₃) scale mediated by reactive elements (REs) can be understood via the strong RE—O bonding energy from the present SFC model applied to oxides (Al₂O₃, Cr₂O₃, Ti₂O₃, ZrO₂, HfO₂, Y₂O₃, and La₂O₃), Al₃M, and Al₄₇MO₇₂ (M = Cr, Ti, Zr, Hf, Y, and La). The present model indicates that Hf is the best RE in retarding alumina scale growth, agreeing with the analyses from bulk modulus, melting point, and enthalpy of formation of oxides, and experimental observations.

• Research Organization: Pennsylvania State University, University Park, PA (United States)
• Sponsoring Organization: USDOE Office of Fossil Energy (FE); National Science Foundation (NSF)
• Grant/Contract Number: FE0024056; AC02-05CH11231
• OSTI ID: 1538803
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: C Vol. 150; ISSN 1359-6462
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English