Effect of a mixed atmosphere H2O-O2-SO2 on the oxidation kinetics and phase formation on CrMnFeCoNi and CrCoNi
- The high-temperature corrosion behaviors of the equimolar CrCoNi medium- and CrMnFeCoNi high-entropy alloy were studied in a gas atmosphere consisting of a volumetric mixture of 10% H2O, 2% O2, 0.5% SO2, and 87.5% Ar at 800 °C for up to 96 h. Both alloys were initially single-phase fcc structured and showed a mean grain size of ~50 µm and a homogeneous chemical composition. The oxide layer thickness of the Cantor alloy CrMnFeCoNi increased linearly with exposure time while it remained constant at ~1 µm for CrCoNi. A Cr2O3 layer and minor amounts of (Co,Ni)Cr2O4 developed on CrCoNi while three layers were detected on the Cantor alloy. These layers were a thin and continuous chromium rich oxide layer at the oxide/alloy interface, a dense (Mn,Cr)3O4 layer in the center and a thick and porous layer of Mn3O4 and MnSO4 at the gas/oxide interface. Additionally, a few metal sulfides were observed in the CrMnFeCoNi matrix. These results were found to be in reasonable agreement withThe high-temperature corrosion behaviors of the equimolar CrCoNi medium- and CrMnFeCoNi high-entropy alloy were studied in a gas atmosphere consisting of a volumetric mixture of 10% H2O, 2% O2, 0.5% SO2, and 87.5% Ar at 800 °C for up to 96 h. Both alloys were initially single-phase fcc structured and showed a mean grain size of ~50 µm and a homogeneous chemical composition. The oxide layer thickness of the Cantor alloy CrMnFeCoNi increased linearly with exposure time while it remained constant at ~1 µm for CrCoNi. A Cr2O3 layer and minor amounts of (Co,Ni)Cr2O4 developed on CrCoNi while three layers were detected on the Cantor alloy. These layers were a thin and continuous chromium rich oxide layer at the oxide/alloy interface, a dense (Mn,Cr)3O4 layer in the center and a thick and porous layer of Mn3O4 and MnSO4 at the gas/oxide interface. Additionally, a few metal sulfides were observed in the CrMnFeCoNi matrix. These results were found to be in reasonable agreement with thermodynamic calculations.…
Autor*innen: | Anna Maria ManzoniORCiD |
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Weitere Person: | W. Mohring, Stephanos KarafiludisORCiD, M. Schneider, G. Laplanche, C. Stephan-Scherb |
Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2023 |
Organisationseinheit der BAM: | 5 Werkstofftechnik |
5 Werkstofftechnik / 5.0 Abteilungsleitung und andere | |
5 Werkstofftechnik / 5.1 Mikrostruktur Design und Degradation | |
6 Materialchemie | |
6 Materialchemie / 6.3 Strukturanalytik | |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten |
Freie Schlagwörter: | Chemically complex alloys; Corrosion; High entropy alloys; Mixed gas atmosphere |
Themenfelder/Aktivitätsfelder der BAM: | Material |
Veranstaltung: | ICHEM 2023 |
Veranstaltungsort: | Knoxville, TN, USA |
Beginndatum der Veranstaltung: | 18.06.2023 |
Enddatum der Veranstaltung: | 22.06.2023 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 28.06.2023 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |