Impact of high pressure torsion processing on helium ion irradiation resistance of molybdenumShow others and affiliations
2022 (English)In: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 191, p. 112151-, article id 112151Article in journal (Refereed) Published
Abstract [en]
The microstructure of Mo was significantly refined by high pressure torsion to verify its irradiation tolerance in comparison with its micrograined counterpart. After deformation microhardness increased from 231 Hv0.2 for a microgarined sample to 542 and 558 Hv0.2, respectively after one and five rotations. Concurrently, the grain refinement was observed, as the grain size decreased with the increase of the deformation degree down to 480 and 110 nm, respectively for one and five rotations. Subsequently, deformed Mo and a micrograined one were irradiated by He ions to the dose of 8 x 1016/cm 2 to verify their potential application as fusion mirrors. Irra-diations were followed by reflectivity measurements in the 300-2400 nm range with a dual beam spectrometer. The measurements revealed that the applied dose causes a decrease in total reflectivity of the micrograined sample, whereas the total reflectivity of deformed samples decreases by additional 2.5%. Nanohardness mea-surements, detailed microscopy observations using focused ion beam and scanning transmission electron mi-croscope as well as positron annihilation spectroscopy investigations were performed to elucidate changes in the microstructure and understand the different mechanisms of bubble creation after irradiation in micrograined and high pressure torsion processed samples.
Place, publisher, year, edition, pages
Elsevier BV , 2022. Vol. 191, p. 112151-, article id 112151
Keywords [en]
Nanomaterials, Ion irradiation, electron microscopy, Vacancy, Severe plastic deformation
National Category
Materials Engineering Fusion, Plasma and Space Physics
Identifiers
URN: urn:nbn:se:kth:diva-321621DOI: 10.1016/j.matchar.2022.112151ISI: 000878505000005Scopus ID: 2-s2.0-85135537305OAI: oai:DiVA.org:kth-321621DiVA, id: diva2:1712614
Note
QC 20221122
2022-11-222022-11-222022-11-22Bibliographically approved