High Temperature Oxidation Behavior of Creep Resistant Steels in Water Vapour Containing Environments
Mária Hagarová,
Gabriela Baranová,
Martin Fujda,
Miloš Matvija,
Peter Horňak,
Jozef Bednarčík,
Daria Yudina
Affiliations
Mária Hagarová
Institute of Materials and Quality Engineering, Faculty of Materials, Metallurgy and Recycling, Technical University of Košice, 042 00 Košice, Slovakia
Gabriela Baranová
Institute of Materials and Quality Engineering, Faculty of Materials, Metallurgy and Recycling, Technical University of Košice, 042 00 Košice, Slovakia
Martin Fujda
Institute of Materials and Quality Engineering, Faculty of Materials, Metallurgy and Recycling, Technical University of Košice, 042 00 Košice, Slovakia
Miloš Matvija
Institute of Materials and Quality Engineering, Faculty of Materials, Metallurgy and Recycling, Technical University of Košice, 042 00 Košice, Slovakia
Peter Horňak
Institute of Materials and Quality Engineering, Faculty of Materials, Metallurgy and Recycling, Technical University of Košice, 042 00 Košice, Slovakia
Jozef Bednarčík
Institute of Physics, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovakia
Daria Yudina
Institute of Physics, Faculty of Science, Pavol Jozef Šafárik University in Košice, 041 54 Košice, Slovakia
This study describes the water vapour effect on the oxidation resistance of 9Cr creep resistant steels. Boiler P91 and MarBN steels were oxidized for 3000 h in a simulated humid atmosphere with ~10% water vapour. The oxidation kinetics had a stable course for 1000 h and was evaluated by the weight gain curves for both experimental steels and both oxidation temperatures. The oxidation rate was higher at 650 °C versus 600 °C, as reflected by the oxidation rate coefficient. A significant increase occurred after 1000 h of oxidation, which was related to the local breakdown oxide scale and oxide nodules were formed on steel. This oxidation behavior was influenced by the fact that a compact spinel structure of iron oxides and alloying elements were not formed on the steel. Analysis after 3000 h of exposure showed hematite Fe2O3 formed on the outer layer, magnetite Fe3O4 on the middle layer, and the bottom layer consisted of iron-chromium-spinel (Fe,Cr)2O3.