|Title||Helium effects on tungsten under fusion-relevant plasma loading conditions|
|Publication Type||Journal Article|
|Year of Publication||2013|
|Authors||G. De Temmerman, K. Bystrov, R.P Doerner, L. Marot, G.M Wright, K.B. Woller, D.G Whyte, J.J Zielinski|
|Journal||Journal of Nuclear Materials|
|Pagination||S78 - S83|
Experiments were performed in the Pilot-PSI linear plasma device to study the formation of helium-induced nanostructures under high heat fluxes (>10 MW m−2), the erosion of a tungsten surface at the elevated temperatures where those structures typically form and most importantly the behavior of a helium-induced fibreform structure during ELM-like pulses. A strong correlation between the characteristic size of the helium-induced morphology and the size of the voids observed in the near-surface region has been found, and both increase in size with increasing temperatures. Temperature-dependent erosion of tungsten surfaces was observed despite the ion energy being below the sputtering threshold, with an exponential increase of the erosion for temperatures higher than 2400 °C. The same effect was observed during ELM-like plasma pulses. Finally, a complete disappearance of the tungsten fibreform structure was observed after only one plasma pulse for energy densities higher than 0.5 MJ m−2.
|Alternate Title||J. Nucl. Mater.|
Go back one page.