Some effects of surface finish and LWR environment on environmentally-assisted crack initiation in Alloy 182

Marc Vankeerberghen, Rik-Wouter Bosch, Alice Dinu, Michael Grimm, Anna Hojna, Jill Meadows, Radek Novotny, Francisco-Javier Perosanz, Zaiqing Que, Stefan Ritter, Fabio Scenini, Aki Toivonen, Liberato Volpe, Bojan Zajec

    Research outputpeer-review


    Under certain conditions, weld alloy 182 has been shown to be prone to environmentally-assisted cracking in light water reactor primary water. Within the European, collaborative project MEACTOS, environmentally-assisted crack initiation was addressed by performing constant elongation rate testing of flat, tapered tensile specimens for four surface finishes (a polished one that serves as a reference, an industrial-milled one, an advanced-machined one and a shot peened one), under both a BWR/NWC (boiling water reactor under normal water chemistry) and a PWR (pressurized water reactor) primary water environment, at various cross-head displacement rates. After testing the critical stress for initiating an environmentally-assisted crack was derived by locating the critical section (the border between areas showing and not showing surface cracking after testing) and calculating the associated local stress. In a first analysis the critical stress was plotted against the nominal strain rate (cross-head displacement rate divided by the length of the tapered gauge section) and an exponential curve was fitted to it; yielding a characteristic critical stress (extrapolation to zero nominal strain rate) and a characteristic nominal strain rate (rendering the nominal strain rate dimensionless under the exponent). In a second analysis an initiation model was fitted to obtain a usage towards EAC initiation of 1 in the experimentally-determined critical cross section. The model is strain rate and stress level dependent. The data and the results of both analyses will be presented and discussed in terms of environmentally-assisted crack initiation.
    Original languageEnglish
    Title of host publicationProceedings of the 20th Iiternational conference on environmental degradation of materials in nuclear power systems-water reactor
    PublisherAMPP - Association for Materials Protection and Performance
    Number of pages23
    StateAccepted/In press - 17 Jul 2022
    Event2022 - 20th International Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactor - The Viewline Resort, Snowmass
    Duration: 17 Jul 202221 Jul 2022


    Conference2022 - 20th International Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactor
    Country/TerritoryUnited States
    Internet address

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