Influence of alloying elements (Cu, Ti, Nb) on the microstructure and corrosion behaviour of AlCrFeNi-based high entropy alloys exposed to oxygen-containing molten Pb. (September 2021)

• Record Type: Journal Article
• Authors: Shi, Hao; Fetzer, Renate; Jianu, Adrian; Weisenburger, Alfons; Heinzel, Annette; Lang, Fabian; Müller, Georg
• Is Part Of: Corrosion science. Volume 190(2021)
• Publication Date: 2021-09
• Subjects: High entropy alloy -- Corrosion -- High temperature -- Microstructure -- Molten Pb; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2021.109659
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: All three alloying elements (Cu, Ti, Nb) result in an FCC dominant microstructure. Al-Cr-Fe-Ni-Cu displays partial oxide scale exfoliation after exposure to molten Pb. A mixed oxide layer has formed on Al-Cr-Fe-Ni-Ti after exposure. Al-Cr-Fe-Ni-Nb shows a promising corrosion resistance to molten Pb at 600 °C. Abstract: Three high entropy alloys (HEAs), based on Al-Cr-Fe-Ni-X (X: Cu, Ti or Nb), have been designed and prepared. The sample with Cu addition has formed FCC solid solutions while the other two have formed FCC matrix plus inter-metallic phases (B2-Ni(Al, Ti) or Laves). The corrosion tests in oxygen-containing molten Pb at 600 °C indicate that Cu or Ti addition degrades the corrosion resistance of HEAs. Sample with Nb addition shows promising corrosion behaviour. Besides, all three alloys have experienced phase transformation after 1000 and 2000 h exposure. New phases like BCC, B2-NiAl, σ-phase, η-phase or-/and- Ni3 Nb have been identified after exposure.