Zircaloy-2 cladding materials

Effect of microstructure on corrosion properties

Martin S. Bojinov, Lena Hansson-Lyyra, Timo Laitinen, Timo Saario, Pekka Sirkiä

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientific

    1 Citation (Scopus)

    Abstract

    The earlier results obtained in the controlled distance electrode (CDE) arrangement showed that the thin-layer electro-chemical impedance and the contact electric impedance measurements provided similar information of the corrosion reactions of the oxide films of different types of Zircaloy-2 specimens. To gain information on the properties of the zirconia corrosion films only, the corrosion reactions taking place in the water was eliminated. To improve the statistical reproducibility of the impedance measurements, a new disc type specimen was introduced. The specimens made of Zr and of Zircaloy-2 tube materials were exposed to simulated BWR water at 300°C for four days, after which their thin oxides were measured by performing the contact impedance measurements in the water. Therefore, the autoclave was evacuated at 300ºC and filled with nitrogen. The additional contact impedance measurements in N2 were performed at temperatures ranging from 300°C down to 100°C. As a result of the measurements in N2, the contribution of the conductivity of the oxide film could be distinguished from the impedance spectrum measured in the water. The thickness of the oxide films was determined later from metallographic samples using scanning electron microscope (SEM). However, the observed difference between the conductivity of the oxide films of the two Zr and Zircaloy-2 specimens were not larger than the accuracy of the impedance measurements.
    Original languageEnglish
    Title of host publicationPlant Life Management
    Subtitle of host publicationProgress for structural integrity
    Place of PublicationEspoo
    PublisherVTT Technical Research Centre of Finland
    Pages165-181
    ISBN (Electronic)951-38-6281-X
    ISBN (Print)951-38-6280-1
    Publication statusPublished - 2003
    MoE publication typeB3 Non-refereed article in conference proceedings
    EventPlant Life Management: Progress for structural integrity - Espoo, Finland
    Duration: 1 Jan 20021 Jan 2002

    Publication series

    NameVTT Symposium
    PublisherVTT
    Number227
    ISSN (Print)0357-9387
    ISSN (Electronic)1455-0873

    Seminar

    SeminarPlant Life Management
    CountryFinland
    CityEspoo
    Period1/01/021/01/02

    Fingerprint

    Zircaloy 2 (trademark)
    impedance measurement
    corrosion
    oxide films
    microstructure
    water
    impedance
    conductivity
    autoclaves
    zirconium oxides
    electric contacts
    electron microscopes
    tubes
    nitrogen
    scanning
    electrodes
    oxides

    Cite this

    Bojinov, M. S., Hansson-Lyyra, L., Laitinen, T., Saario, T., & Sirkiä, P. (2003). Zircaloy-2 cladding materials: Effect of microstructure on corrosion properties. In Plant Life Management: Progress for structural integrity (pp. 165-181). Espoo: VTT Technical Research Centre of Finland. VTT Symposium, No. 227
    Bojinov, Martin S. ; Hansson-Lyyra, Lena ; Laitinen, Timo ; Saario, Timo ; Sirkiä, Pekka. / Zircaloy-2 cladding materials : Effect of microstructure on corrosion properties. Plant Life Management: Progress for structural integrity. Espoo : VTT Technical Research Centre of Finland, 2003. pp. 165-181 (VTT Symposium; No. 227).
    @inproceedings{a99df1c44cad46e08b2056810572b635,
    title = "Zircaloy-2 cladding materials: Effect of microstructure on corrosion properties",
    abstract = "The earlier results obtained in the controlled distance electrode (CDE) arrangement showed that the thin-layer electro-chemical impedance and the contact electric impedance measurements provided similar information of the corrosion reactions of the oxide films of different types of Zircaloy-2 specimens. To gain information on the properties of the zirconia corrosion films only, the corrosion reactions taking place in the water was eliminated. To improve the statistical reproducibility of the impedance measurements, a new disc type specimen was introduced. The specimens made of Zr and of Zircaloy-2 tube materials were exposed to simulated BWR water at 300°C for four days, after which their thin oxides were measured by performing the contact impedance measurements in the water. Therefore, the autoclave was evacuated at 300ºC and filled with nitrogen. The additional contact impedance measurements in N2 were performed at temperatures ranging from 300°C down to 100°C. As a result of the measurements in N2, the contribution of the conductivity of the oxide film could be distinguished from the impedance spectrum measured in the water. The thickness of the oxide films was determined later from metallographic samples using scanning electron microscope (SEM). However, the observed difference between the conductivity of the oxide films of the two Zr and Zircaloy-2 specimens were not larger than the accuracy of the impedance measurements.",
    author = "Bojinov, {Martin S.} and Lena Hansson-Lyyra and Timo Laitinen and Timo Saario and Pekka Sirki{\"a}",
    note = "Project code: H2SU00363",
    year = "2003",
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    series = "VTT Symposium",
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    Bojinov, MS, Hansson-Lyyra, L, Laitinen, T, Saario, T & Sirkiä, P 2003, Zircaloy-2 cladding materials: Effect of microstructure on corrosion properties. in Plant Life Management: Progress for structural integrity. VTT Technical Research Centre of Finland, Espoo, VTT Symposium, no. 227, pp. 165-181, Plant Life Management, Espoo, Finland, 1/01/02.

    Zircaloy-2 cladding materials : Effect of microstructure on corrosion properties. / Bojinov, Martin S.; Hansson-Lyyra, Lena; Laitinen, Timo; Saario, Timo; Sirkiä, Pekka.

    Plant Life Management: Progress for structural integrity. Espoo : VTT Technical Research Centre of Finland, 2003. p. 165-181 (VTT Symposium; No. 227).

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientific

    TY - GEN

    T1 - Zircaloy-2 cladding materials

    T2 - Effect of microstructure on corrosion properties

    AU - Bojinov, Martin S.

    AU - Hansson-Lyyra, Lena

    AU - Laitinen, Timo

    AU - Saario, Timo

    AU - Sirkiä, Pekka

    N1 - Project code: H2SU00363

    PY - 2003

    Y1 - 2003

    N2 - The earlier results obtained in the controlled distance electrode (CDE) arrangement showed that the thin-layer electro-chemical impedance and the contact electric impedance measurements provided similar information of the corrosion reactions of the oxide films of different types of Zircaloy-2 specimens. To gain information on the properties of the zirconia corrosion films only, the corrosion reactions taking place in the water was eliminated. To improve the statistical reproducibility of the impedance measurements, a new disc type specimen was introduced. The specimens made of Zr and of Zircaloy-2 tube materials were exposed to simulated BWR water at 300°C for four days, after which their thin oxides were measured by performing the contact impedance measurements in the water. Therefore, the autoclave was evacuated at 300ºC and filled with nitrogen. The additional contact impedance measurements in N2 were performed at temperatures ranging from 300°C down to 100°C. As a result of the measurements in N2, the contribution of the conductivity of the oxide film could be distinguished from the impedance spectrum measured in the water. The thickness of the oxide films was determined later from metallographic samples using scanning electron microscope (SEM). However, the observed difference between the conductivity of the oxide films of the two Zr and Zircaloy-2 specimens were not larger than the accuracy of the impedance measurements.

    AB - The earlier results obtained in the controlled distance electrode (CDE) arrangement showed that the thin-layer electro-chemical impedance and the contact electric impedance measurements provided similar information of the corrosion reactions of the oxide films of different types of Zircaloy-2 specimens. To gain information on the properties of the zirconia corrosion films only, the corrosion reactions taking place in the water was eliminated. To improve the statistical reproducibility of the impedance measurements, a new disc type specimen was introduced. The specimens made of Zr and of Zircaloy-2 tube materials were exposed to simulated BWR water at 300°C for four days, after which their thin oxides were measured by performing the contact impedance measurements in the water. Therefore, the autoclave was evacuated at 300ºC and filled with nitrogen. The additional contact impedance measurements in N2 were performed at temperatures ranging from 300°C down to 100°C. As a result of the measurements in N2, the contribution of the conductivity of the oxide film could be distinguished from the impedance spectrum measured in the water. The thickness of the oxide films was determined later from metallographic samples using scanning electron microscope (SEM). However, the observed difference between the conductivity of the oxide films of the two Zr and Zircaloy-2 specimens were not larger than the accuracy of the impedance measurements.

    M3 - Conference article in proceedings

    SN - 951-38-6280-1

    T3 - VTT Symposium

    SP - 165

    EP - 181

    BT - Plant Life Management

    PB - VTT Technical Research Centre of Finland

    CY - Espoo

    ER -

    Bojinov MS, Hansson-Lyyra L, Laitinen T, Saario T, Sirkiä P. Zircaloy-2 cladding materials: Effect of microstructure on corrosion properties. In Plant Life Management: Progress for structural integrity. Espoo: VTT Technical Research Centre of Finland. 2003. p. 165-181. (VTT Symposium; No. 227).