Evolution of plastic deformation in heavily deformed and recrystallized tungsten of ITER specification studied by TEM. (August 2017)

• Record Type: Journal Article
• Authors: Dubinko, A.; Terentyev, D.; Bakaeva, A.; Verbeken, K.; Wirtz, M.; Hernández-Mayoral, M.
• Is Part Of: International journal of refractory metals & hard materials. Volume 66(2017)
• Page Start: 105
• Page End: 115
• Publication Date: 2017-08
• Subjects: Tungsten -- Deformation -- Plasticity -- Dislocations; Heat resistant alloys -- Periodicals; Refractory materials -- Periodicals; Metallography -- Periodicals; Alliages réfractaires -- Périodiques; Matériaux réfractaires -- Périodiques; Métallographie -- Périodiques; Heat resistant alloys; Metallography; Refractory materials; Periodicals; Electronic journals; 669.73
• DOI: 10.1016/j.ijrmhm.2017.03.004
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: Microstructure induced by plastic deformation at 600 °C in as-fabricated and recrystallized tungsten grades of ITER specification is studied by means of transmission electron microscopy (TEM). Both grades are produced by AG Plansee and being used by fusion community as research material for plasma facing and high heat flux components. Reference microstructure was investigated by a combination of TEM, scanning electron microscopy and nano-indentation techniques. TEM was applied to investigate the necking region in the tensile samples deformed up to ~ 30% of stain. The deformation-induced microstructure was characterized and compared for the two grades in terms of the dislocation density, heterogeneity, observation of pile-ups and tangles specifically near high angle grain boundaries. The obtained evolution of the dislocation density was compared with the prediction of the previously developed thermo-mechanical model for the plastic deformation of polycrystalline tungsten and a good agreement was found without modification of the original parameter set. Highlights: ITER specification tungsten is studied under plastic deformation. Evolution of microstructure at 600 °C under plastic flow Sub-grains control plastic deformation at 600 °C.