@article{8921,
  author = {J.G. A. Scholte and M. Iafrati and S.S.H. Lam and B. Tyburska-Pueschel and M. Riepen and F. Brochard and M.M.P. Vissers and T.W. Morgan},
  title = {Reducing tin droplet ejection from capillary porous structures under hydrogen plasma exposure in Magnum-PSI},
  abstract = {Liquid metal based divertors could be a more robust alternative to a solid tungsten design for DEMO. The liquid is confined in a sponge-like tungsten layer, called a capillary porous structure (CPS). It has been found previously that under certain conditions, many tin droplets eject from a CPS when it is brought into contact with a hydrogen plasma. These would present a contamination issue for the plasma core. Stability analysis suggests that droplet ejection can be suppressed by reduction of the pore size. To test this, stainless-steel CPS targets with pore size ranging from 0.5-100um filled with tin were exposed to identical loading conditions. This was done in the linear plasma device Magnum-PSI, capable of reaching divertor relevant plasma conditions. Furthermore, the influence of the CPS manufacturing techniques is considered by comparing the performance of a 3D printed, a mesh felts and a sintered CPS, all made from tungsten. Each target was surrounded by four witness plates, which were analysed post-mortem for Sn content by Rutherford backscattering. During plasma exposure, tin droplets were observed using a fast visible camera and plasma light emission via survey optical emission spectroscopy. The results imply that Sn erosion can be reduced by a factor of 50 when reducing the pore size. Moreover, it highlights the importance of avoiding overfilling of CPS targets with Sn.},
  year = {2023},
  journal = {Nuclear Materials and Energy},
  volume = {34},
  pages = {101315},
  month = {03/2023},
  doi = {10.1016/j.nme.2022.101315},
  language = {eng},
}