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

SCRIPTA MATERIALIA

卷:150

Article

Shang, Shun-Li¹  Wang, Yi¹  Gleeson, Brian²  Liu, Zi-Kui¹ 

[1] Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA

[2] Univ Pittsburgh, Dept Mech Engn & Mat Sci, Pittsburgh, PA 15261 USA

关键词: Alumina scale;    Reactive elements;    Oxides;    Phonon;    First principles calculations;   

DOI  :  10.1016/j.scriptamat.2018.03.002

来源: Elsevier

【 摘 要 】

Interatomic bonding strength/energy can be quantified by stretching force constants (SFC) after first-principles phonon calculations. Here, we show that the slow-growing alumina (alpha-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. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free