Oxidation behavior of Ni-25Cr-10Fe-3Si-χNb alloys at 1000 °C in ambient air: Role of Laves phase. (15th July 2021)

• Record Type: Journal Article
• Authors: Jia, Guodong; Xu, Wanjian; Ouyang, Minghui; Wang, Huichao; Wang, Longbao; Xiao, Xueshan
• Is Part Of: Corrosion science. Volume 187(2021)
• Publication Date: 2021-07-15
• Subjects: A. Ni-Cr-Fe-Si alloys -- B. Nb -- C. Oxidation -- D. Laves phase; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2021.109475
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: The formation of Laves phase shows a great impact on the high-temperature oxidation behavior of Ni-25Cr-10Fe-3Si-χNb alloys. The dissociation of Laves phase promoted the formation of Nb2 O5, which reduced the spalling resistance of the oxide scale. The Laves phase increased the internal oxidation regions. Abstract: The oxidation behavior of Ni-25Cr-10Fe-3Si-χNb (0–3.0 wt.%) alloys were investigated at 1000 °C in ambient air. Mass gain obeys the parabolic law, and the parabolic rate constant increased with the Nb content due to the formation of the Laves phase. During oxidation, Nb atoms were released from the Laves phase lattice and reacted with oxygen to form Nb2 O5 . Oxygen could diffuse into the alloy and be combined with the Si in the Laves phase to form internal oxidation. The outer layer of oxide scales is Cr2 O3 and Nb2 O5, and the inner layer is SiO2 .