Degradation of single-crystal gas turbine blades

Juhani Rantala, Jorma Salonen, Sanni Yli-Olli, Stefan Holmström, Petra Jauhiainen

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

    Abstract

    The work presented in this paper aimed to evaluate and classify the microstructural degradation of diffusion coated single-crystal gas turbine blade, so that the characterised features of degradation could be used for assessing the effective in-service material temperatures at the corresponding blade locations. Two potentially useful indicative measures were evaluated for this purpose: a) gamma prime coarsening and degradation in the substrate microstructure to indicate the condition and temperature in the blade interior and b) combined thickness of the intermediate diffusion zone (IDZ) and topologically close-packed (TCP) precipitate layers to indicate the condition and temperature at the blade coating. Both applied measures appear to provide meaningful indications of the service temperature, although not with the same level of uncertainty. The thickness of IDZ+TPC layers can indicate the effective temperatures to a relatively good accuracy as long as the IDZ and TPC layers remain sufficiently intact for the assessment. For verification and demonstration purposes, a case example is shown of an ex-service turbine blade.
    Original languageEnglish
    Title of host publicationBaltica IX. International Conference on Life Management and Maintenance for Power Plants
    EditorsPertti Auerkari, Juha Veivo
    Place of PublicationEspoo
    PublisherVTT Technical Research Centre of Finland
    Pages233-250
    ISBN (Print)978-951-38-8025-5, 978-951-38-8026-2
    Publication statusPublished - 2013
    MoE publication typeA4 Article in a conference publication
    EventBALTICA IX - International Conference on Life Management and Maintenance for Power Plants - Helsinki-Stockholm, Finland
    Duration: 11 Jun 201313 Jun 2013

    Publication series

    SeriesVTT Technology
    Number106
    ISSN2242-1211

    Conference

    ConferenceBALTICA IX - International Conference on Life Management and Maintenance for Power Plants
    CountryFinland
    CityHelsinki-Stockholm
    Period11/06/1313/06/13

    Fingerprint

    Turbomachine blades
    Gas turbines
    Single crystals
    Degradation
    Temperature
    Coarsening
    Precipitates
    Turbines
    Demonstrations
    Coatings
    Microstructure
    Substrates

    Cite this

    Rantala, J., Salonen, J., Yli-Olli, S., Holmström, S., & Jauhiainen, P. (2013). Degradation of single-crystal gas turbine blades. In P. Auerkari, & J. Veivo (Eds.), Baltica IX. International Conference on Life Management and Maintenance for Power Plants (pp. 233-250). Espoo: VTT Technical Research Centre of Finland. VTT Technology, No. 106
    Rantala, Juhani ; Salonen, Jorma ; Yli-Olli, Sanni ; Holmström, Stefan ; Jauhiainen, Petra. / Degradation of single-crystal gas turbine blades. Baltica IX. International Conference on Life Management and Maintenance for Power Plants. editor / Pertti Auerkari ; Juha Veivo. Espoo : VTT Technical Research Centre of Finland, 2013. pp. 233-250 (VTT Technology; No. 106).
    @inproceedings{2059563914e74f289c908dbba8391bea,
    title = "Degradation of single-crystal gas turbine blades",
    abstract = "The work presented in this paper aimed to evaluate and classify the microstructural degradation of diffusion coated single-crystal gas turbine blade, so that the characterised features of degradation could be used for assessing the effective in-service material temperatures at the corresponding blade locations. Two potentially useful indicative measures were evaluated for this purpose: a) gamma prime coarsening and degradation in the substrate microstructure to indicate the condition and temperature in the blade interior and b) combined thickness of the intermediate diffusion zone (IDZ) and topologically close-packed (TCP) precipitate layers to indicate the condition and temperature at the blade coating. Both applied measures appear to provide meaningful indications of the service temperature, although not with the same level of uncertainty. The thickness of IDZ+TPC layers can indicate the effective temperatures to a relatively good accuracy as long as the IDZ and TPC layers remain sufficiently intact for the assessment. For verification and demonstration purposes, a case example is shown of an ex-service turbine blade.",
    author = "Juhani Rantala and Jorma Salonen and Sanni Yli-Olli and Stefan Holmstr{\"o}m and Petra Jauhiainen",
    year = "2013",
    language = "English",
    isbn = "978-951-38-8025-5",
    series = "VTT Technology",
    publisher = "VTT Technical Research Centre of Finland",
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    editor = "Pertti Auerkari and Juha Veivo",
    booktitle = "Baltica IX. International Conference on Life Management and Maintenance for Power Plants",
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    Rantala, J, Salonen, J, Yli-Olli, S, Holmström, S & Jauhiainen, P 2013, Degradation of single-crystal gas turbine blades. in P Auerkari & J Veivo (eds), Baltica IX. International Conference on Life Management and Maintenance for Power Plants. VTT Technical Research Centre of Finland, Espoo, VTT Technology, no. 106, pp. 233-250, BALTICA IX - International Conference on Life Management and Maintenance for Power Plants, Helsinki-Stockholm, Finland, 11/06/13.

    Degradation of single-crystal gas turbine blades. / Rantala, Juhani; Salonen, Jorma; Yli-Olli, Sanni; Holmström, Stefan; Jauhiainen, Petra.

    Baltica IX. International Conference on Life Management and Maintenance for Power Plants. ed. / Pertti Auerkari; Juha Veivo. Espoo : VTT Technical Research Centre of Finland, 2013. p. 233-250 (VTT Technology; No. 106).

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

    TY - GEN

    T1 - Degradation of single-crystal gas turbine blades

    AU - Rantala, Juhani

    AU - Salonen, Jorma

    AU - Yli-Olli, Sanni

    AU - Holmström, Stefan

    AU - Jauhiainen, Petra

    PY - 2013

    Y1 - 2013

    N2 - The work presented in this paper aimed to evaluate and classify the microstructural degradation of diffusion coated single-crystal gas turbine blade, so that the characterised features of degradation could be used for assessing the effective in-service material temperatures at the corresponding blade locations. Two potentially useful indicative measures were evaluated for this purpose: a) gamma prime coarsening and degradation in the substrate microstructure to indicate the condition and temperature in the blade interior and b) combined thickness of the intermediate diffusion zone (IDZ) and topologically close-packed (TCP) precipitate layers to indicate the condition and temperature at the blade coating. Both applied measures appear to provide meaningful indications of the service temperature, although not with the same level of uncertainty. The thickness of IDZ+TPC layers can indicate the effective temperatures to a relatively good accuracy as long as the IDZ and TPC layers remain sufficiently intact for the assessment. For verification and demonstration purposes, a case example is shown of an ex-service turbine blade.

    AB - The work presented in this paper aimed to evaluate and classify the microstructural degradation of diffusion coated single-crystal gas turbine blade, so that the characterised features of degradation could be used for assessing the effective in-service material temperatures at the corresponding blade locations. Two potentially useful indicative measures were evaluated for this purpose: a) gamma prime coarsening and degradation in the substrate microstructure to indicate the condition and temperature in the blade interior and b) combined thickness of the intermediate diffusion zone (IDZ) and topologically close-packed (TCP) precipitate layers to indicate the condition and temperature at the blade coating. Both applied measures appear to provide meaningful indications of the service temperature, although not with the same level of uncertainty. The thickness of IDZ+TPC layers can indicate the effective temperatures to a relatively good accuracy as long as the IDZ and TPC layers remain sufficiently intact for the assessment. For verification and demonstration purposes, a case example is shown of an ex-service turbine blade.

    M3 - Conference article in proceedings

    SN - 978-951-38-8025-5

    SN - 978-951-38-8026-2

    T3 - VTT Technology

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    EP - 250

    BT - Baltica IX. International Conference on Life Management and Maintenance for Power Plants

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    Rantala J, Salonen J, Yli-Olli S, Holmström S, Jauhiainen P. Degradation of single-crystal gas turbine blades. In Auerkari P, Veivo J, editors, Baltica IX. International Conference on Life Management and Maintenance for Power Plants. Espoo: VTT Technical Research Centre of Finland. 2013. p. 233-250. (VTT Technology; No. 106).