Early Material Damage in Equimolar CrMnFeCoNi in Mixed Oxidizing/Sulfiding Hot Gas Atmosphere
- The challenges to use more varied fuels at medium and high temperatures above 500 °C need to be addressed by tuning the materials towards a better resistance against increased corrosion. As a first step the corrosion processes need to be better understood, especially in the case of the unavoidable and highly corrosive sulfur-based gases. In this work oxidation/sulfidation of an equimolar CrMnFeCoNi high entropy alloy is studied at an early stage after hot gas exposure at 600 °C for 6 h in 0.5% SO2 and 99.5% Ar. The oxidation process is studied by means of x-ray diffraction, scanning and transmission electron microscopy and supported by thermodynamic calculations. It is found that the sulfur does not enter the bulk material but interacts mainly with the fast-diffusing manganese at grain boundary triple junctions at the alloy surface. Sub-micrometer scaled Cr-S-O rich phases close to the grain boundaries complete the sulfur-based phase formation. The grains are covered in different Fe,The challenges to use more varied fuels at medium and high temperatures above 500 °C need to be addressed by tuning the materials towards a better resistance against increased corrosion. As a first step the corrosion processes need to be better understood, especially in the case of the unavoidable and highly corrosive sulfur-based gases. In this work oxidation/sulfidation of an equimolar CrMnFeCoNi high entropy alloy is studied at an early stage after hot gas exposure at 600 °C for 6 h in 0.5% SO2 and 99.5% Ar. The oxidation process is studied by means of x-ray diffraction, scanning and transmission electron microscopy and supported by thermodynamic calculations. It is found that the sulfur does not enter the bulk material but interacts mainly with the fast-diffusing manganese at grain boundary triple junctions at the alloy surface. Sub-micrometer scaled Cr-S-O rich phases close to the grain boundaries complete the sulfur-based phase formation. The grains are covered in different Fe, Mn and Cr based spinels and other oxides.…
Autor*innen: | Anna Maria ManzoniORCiD |
---|---|
Weitere Person: | W. Mohring, René Hesse, Leonardo Agudo JácomeORCiD, C. Stephan-Scherb |
Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2022 |
Organisationseinheit der BAM: | 5 Werkstofftechnik |
5 Werkstofftechnik / 5.1 Mikrostruktur Design und Degradation | |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten |
Freie Schlagwörter: | Cantor alloy; Corrosion; High entropy alloy; Sulfiding; Transmission electron microscopy |
Themenfelder/Aktivitätsfelder der BAM: | Material |
Material / Degradation von Werkstoffen | |
Veranstaltung: | Priority Programme (Schwerpunktprogramm) Compositionally Complex Alloys - High Entropy Alloys (SPP CCA - HEA) |
Veranstaltungsort: | Bayreuth, Germany |
Beginndatum der Veranstaltung: | 12.07.2022 |
Enddatum der Veranstaltung: | 13.07.2022 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 29.07.2022 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |