Finite element analysis of heat load of tungsten relevant to ITER conditions

    Research outputpeer-review

    Abstract

    A computational procedure is proposed in order to predict the initiation of intergranular cracks in tungsten with ITER specification microstructure (i.e. characterised by elongated micrometresized grains). Damage is caused by a cyclic heat load, which emerges from plasma instabilities during operation of thermonuclear devices. First, a macroscopic thermo-mechanical simulation is performed in order to obtain temperature- and strain field in the material. The strain path is recorded at a selected point of interest of the macroscopic specimen, and is then applied at the microscopic level to a finite element mesh of a polycrystal. In the microscopic simulation, the stress state at the grain boundaries serves as the marker of cracking initiation. The simulated heat load cycle is a representative of edge-localized modes, which are anticipated during normal operations of ITER. Normal stresses at the grain boundary interfaces were shown to strongly depend on the direction of grain orientation with respect to the heat flux direction and to attain higher values if the flux is perpendicular to the elongated grains, where it apparently promotes crack initiation.
    Original languageEnglish
    Title of host publicationPhysica Scripta
    Subtitle of host publication16th International Conference on Plasma-Facing Materials and Components for Fusion Applications
    Pages1-5
    Number of pages5
    Volume2017
    EditionT170
    DOIs
    StatePublished - 25 Aug 2017

    Publication series

    NamePhysica Scripta
    PublisherIOP - IOP Publishing
    ISSN (Print)0031-8949

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