Impact of high pressure torsion processing on helium ion irradiation resistance of molybdenum mirrors

Datum

16.06.2023

Zeit

13:30 - 14:30

Sprecher

Krawczyńska Agnieszka

Sprache

en

Hauptthema

Materialien

Host

Maciej Oskar Liedke

Beschreibung

Transmission of optical signals from plasma in controlled fusion devices is the fundament of plasma diagnosis using optical spectroscopy and imaging techniques. They serve both physics studies and machine control and protection. Therefore, quality of optical components, such as mirrors and windows, is essential to ensure both reliable plasma operation and high-level research. Various materials for mirrors were tested, among the main candidates are polycrystalline and single crystal Mo. In this work nanostructured Mo mirrors are considered as a polycrystalline variant. The proposed technique for microstructure refinement is high pressure torsion, which is one of the most efficient severe plastic deformation techniques. Detailed microscopy observations using focused ion beam (NB5000 Hitachi) and scanning transmission electron microscope (SU8000 Hitachi, HD2700 Hitachi) as well as positron annihilation spectroscopy investigations were performed to elucidate microstructure changes in such mirrors after irradiation.

Letztmalig verändert: 16.06.2023, 07:40:11