Evolution of transiently melt damaged tungsten under ITER-relevant divertor plasma heat loading

A high-repetition-rate ELM simulation system was used at both the Pilot-PSI and Magnum-PSI linear plasma devices to investigate the nature of W damage under multiple shallow melt events and the subsequent surface evolution under ITER relevant plasma fluence and high ELM number. First, repetitive sha...

Full description

Saved in:
Bibliographic Details
Published inJournal of nuclear materials Vol. 463; pp. 193 - 197
Main Authors Bardin, S., Morgan, T.W., Glad, X., Pitts, R.A., De Temmerman, G.
Format Journal Article
LanguageEnglish
Published Elsevier B.V 01.08.2015
Subjects
Damage
Devices
Elm
Evolution
Exposure
Melting
Melts
Thermal properties
Online AccessGet full text

Cover

More Information
Summary:A high-repetition-rate ELM simulation system was used at both the Pilot-PSI and Magnum-PSI linear plasma devices to investigate the nature of W damage under multiple shallow melt events and the subsequent surface evolution under ITER relevant plasma fluence and high ELM number. First, repetitive shallow melting of two W monoblocks separated by a 0.5mm gap was obtained by combined pulsed/steady-state hydrogen plasma loading at normal incidence in the Pilot-PSI device. Surface modifications including melting, cracking and strong net-reshaping of the surface are obtained. During the second step, the pre-damaged W sample was exposed to a high flux plasma regime in the Magnum-PSI device with a grazing angle of 35°. SEM analysis indicates no measurable change to the surface state after the exposure in Magnum-PSI. An increase in transient-induced temperature rise of 40% is however observed, indicating a degradation of thermal properties over time.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0022-3115
1873-4820
DOI:10.1016/j.jnucmat.2014.10.046