Isothermal Oxidation Behavior of FGH720Li Superalloy at Service Temperatures

Abstract:

The oxidation behavior of FGH720Li(P/M Udimet720Li) superalloy was investigated under static atmosphere in temperature ranging from 600°C to 730°C. The oxidation kinetics, composition and morphology of the oxidation layers were characterized by means of isothermal oxidation tests, X-ray diffraction(XRD), scanning electron microscopy（SEM）and energy dispersive X-ray spectroscopy(EDS). The results showed that the oxidation kinetics curves of FGH720Li superalloy followed the parabolic law. The results of cross-sectional morphology and elemental distribution indicated that the oxidation layer could be divided into three parts：porous Cr₂O₃ outer layer, dense Cr₂O₃ medium layer and oxidation affected zone with nail-like Al₂O₃ inner layer. The oxidation process was primarily controlled by the diffusion of chromium and oxygen through the oxide scale.

• Periodical: Materials Science Forum (Volume 1035)
• Pages: 96-101
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1035.96
• Online since: June 2021
• Authors: Yue Tang*, Zi Chao Peng, Xu Qing Wang, Guo Jun Ma, Dan Wu
• Keywords: Diffusion, FGH720Li Superalloy, Isothermal Oxidation, Oxidation Layer

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