Influence of temperature and surface treatment on steamside oxidation

Satu Tuurna, Sanni Yli-Olli, Pertti Auerkari, Edgardo Coda Zabetta, Kyösti Vänskä

    Research output: Contribution to conferenceConference articleScientificpeer-review

    Abstract

    Steam oxidation has become an important issue for steam power plants as operating temperatures increase from current to 650°C and even higher. Apart from the chemical composition of the material, surface condition is a major factor affecting the oxidation resistance in steam and supercritical water. In this paper, stainless boiler steels (UNS S34710, UNS S31035) are investigated in elevated steam oxidation conditions. Tests were conducted in a supercritical water autoclave environment (250 bar, with 125 ppb dissolved oxygen and a pH of 7) at 625°C, 650°C and 675°C up to 1000 h. Materials were tested with different surface finishes shot peened, milled and spark eroded. The results show an influence of surface finish on the early stages of oxidation. Oxides formed on more rough surfaces were more adherent, and thinner than on a ground surface. To that extent that the oxide formed on the milled, most cold worked, surface of UNS S34710 (Cr 18 wt-%) was thinner than on the spark eroded and ground surface of S31035 (Cr 22 wt-%). More variation on oxidation rate could be seen with increasing temperature.
    Original languageEnglish
    Number of pages11
    Publication statusPublished - 2014
    MoE publication typeNot Eligible
    Event10th Liege Conference on Materials for Advanced Power Engineering - Liege, Belgium
    Duration: 14 Sep 201417 Sep 2014
    Conference number: 10

    Conference

    Conference10th Liege Conference on Materials for Advanced Power Engineering
    CountryBelgium
    CityLiege
    Period14/09/1417/09/14

    Keywords

    • steam oxidation
    • surface treatment
    • superheater

    Fingerprint Dive into the research topics of 'Influence of temperature and surface treatment on steamside oxidation'. Together they form a unique fingerprint.

    Cite this