Pulsed-laser ablation of co-deposits on JT-60 graphite tile

Sakawa, Y.; Watanabe, Daisuke; Shibahara, T.; Sugiyama, K.; Tanabe, T.

doi:10.1016/j.jnucmat.2007.04.014

Cited by 4 publications

(3 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the previous work, we investigated effects of laser wavelength on ablation of codeposition using the fundamental (1064 nm) and the forth-harmonic (266 nm) emission of Nd:YAG laser with 20 pico-sec pulse duration [12]. According to the result, the laser irradiation with short-wavelength (266 nm) showed better LID property.…”

Section: /14mentioning

confidence: 99%

“…4 (a) turned to decreasing with the laser fluence. We defined each fluence range below and above this threshold as "weak"-ablation range (WAR) and "strong"-ablation range (SAR), respectively [10][11][12]. In 7/14 SAR, visible light emissions from C + and C 2+ were observed, and C + or C 2+ ions were dominant in TOFMS spectrum, i.e.…”

Section: Emitted Ions and Desorbed Gases Analysesmentioning

confidence: 99%

“…Although this method is effective for tritium retained in the near surface, complete removal from thick codeposited layer is difficult. Another approach is the ablation-assisted removal by using high-power pulsed-laser irradiation [5][6][7][8][9][10][11][12], which is the topic of this paper. It is possible to remove not only tritium but also deposited layer itself by ablation, hence almost complete removal is expected.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Removal of the deposition on JT-60 tile by nano-sec pulsed-laser irradiation

Sugiyama

Sakawa

Tanabe

et al. 2010

Journal of Nuclear Materials

View full text Add to dashboard Cite

To clarify the property of tritium removal from carbon codeposition by using pulsed-laser induced desorption, hydrogen removal from co-deposits on JT-60 divertor tile using a fourth-harmonic emission (266 nm) of a nano-sec Nd:YAG laser was demonstrated. The threshold laser fluence for ablation was ~ 0.3 J/cm 2 , which was slightly higher compared to that of the pico-sec laser irradiation. The energy absorption coefficient for the nano-sec laser, which was obtained by fitting the removal rate by so-called Beer's law, was larger than the pico-sec laser. Since the time constant of thermal wave propagation into the target is of the order of nanosecond, such differences between nano-and pico-sec lasers could be attributed to thermal effects. The ablation threshold of the deposited layer was lower than that of a pure graphite, which could be attributed to the difference of thermal conductivity between deposited layer and pure graphite. The removal rate of the nano-sec laser was higher than that of pico-sec laser in the fluence range of < 0.5 J/cm 2 . On the other hand, the production ratio [hydrocarbon species] / [H 2 ] continuously increased with the laser fluence, and no significant ionization of carbon was observed in this fluence range. This indicated that the fluence range in this study was "weak"-ablation range, which was still not sufficient to minimize the hydrocarbon production.

show abstract

Section: /14mentioning

confidence: 99%

Section: Emitted Ions and Desorbed Gases Analysesmentioning

confidence: 99%