Differences in Ultrasonic Indications: Thermal Fatigue Cracks and EDM Notches

Ari Koskinen, Jonne Haapalainen, Iikka Virkkunen, Mika Kemppainen

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


    Different types of artificial defects are used for a qualification of NDT methods. The representativeness of these defects, as compared to service induce flaws, is crucial when the performance of NDT method or inspector is evaluated. Ultrasonic indications are highly dependent on defect characteristics like roughness, crack opening, tilt and branching. These characteristics are even more significant than the defect size. To develop performance and reliability of ultrasonic inspection methods and procedures more research on different type of discontinuity indications is needed. In this study, indications from different types of discontinuities are measured using C-mode scanning acoustic microscope (C-SAM). The inspection item is austenitic stainless steel pipe with thermal fatigue cracks and similar size of EDM notches. Clear difference can be seen between indications from the EDM notches and from the thermal fatigue cracks.
    Original languageEnglish
    Title of host publicationProceedings
    Subtitle of host publication18th World Conference on Nondestructive Testing, WCNDT
    Number of pages8
    Publication statusPublished - 2012
    MoE publication typeA4 Article in a conference publication
    Event18th World Conference on Non-Destructive Testing, WCNDT - Durban, South Africa
    Duration: 16 Apr 201220 Apr 2012


    Conference18th World Conference on Non-Destructive Testing, WCNDT
    Abbreviated titleWCNDT
    Country/TerritorySouth Africa


    • ultrasound
    • ultrasonic inspection
    • C-mode scanning acoustic microscope (C-SAM)
    • thermal fatigue
    • indication
    • discontinuity
    • defect
    • qualification


    Dive into the research topics of 'Differences in Ultrasonic Indications: Thermal Fatigue Cracks and EDM Notches'. Together they form a unique fingerprint.

    Cite this