TY  - JOUR
AU  - Huber, Alexander
AU  - Arakcheev, A.
AU  - Sergienko, Gennady
AU  - Steudel, Isabel
AU  - Wirtz, Marius
AU  - Burdakov, A. V.
AU  - Coenen, Jan Willem
AU  - Kreter, Arkadi
AU  - Linke, Jochen
AU  - Mertens, Philippe
AU  - Philipps, V.
AU  - Pintsuk, Gerald
AU  - Reinhart, Michael
AU  - Samm, Ulrich
AU  - Shoshin, A.
AU  - Schweer, Bernd
AU  - Unterberg, Bernhard
AU  - Zlobinski, M.
TI  - Investigation of the Impact of Transient Heat Loads Applied by Laser Irradiation on ITER-Grade Tungsten
JO  - Physica scripta
VL  - T159
SN  - 1402-4896
CY  - Bristol
PB  - IoP Publ.
M1  - FZJ-2014-03804
SP  - 014005
PY  - 2014
AB  - Cracking thresholds and crack patterns in tungsten targets after repetitive ITER-like edge localized mode (ELM) pulses have been studied in recent simulation experiments by laser irradiation. The tungsten specimens were tested under selected conditions to quantify the thermal shock response. A Nd:YAG laser capable of delivering up to 32 J of energy per pulse with a duration of 1 ms at the fundamental wavelength λ = 1064 nm has been used to irradiate ITER-grade tungsten samples with repetitive heat loads. The laser exposures were performed for targets at room temperature (RT) as well as for targets preheated to 400 °C to measure the effects of the ELM-like loading conditions on the formation and development of cracks. The magnitude of the heat loads was 0.19, 0.38, 0.76 and 0.90 MJ m−2 (below the melting threshold) with a pulse duration of 1 ms. The tungsten surface was analysed after 100 and 1000 laser pulses to investigate the influence of material modification by plasma exposures on the cracking threshold. The observed damage threshold for ITER-grade W lies between 0.38 and 0.76 GW m−2. Continued cycling up to 1000 pulses at RT results in enhanced erosion of crack edges and crack edge melting. At the base temperature of 400 °C, the formation of cracks is suppressed.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000334847800006
DO  - DOI:10.1088/0031-8949/2014/T159/014005
UR  - https://juser.fz-juelich.de/record/154483
ER  -