Installation of a plasmatron at the Belgian Nuclear Research Centre and its use for plasma-wall interaction studies

In JET and ITER, the first wall will be covered by Be and a full or partial W divertor will be common. In DEMO, only high-Z, low erosion material such as W will be present as a plasma facing material. In present day tokamaks, the very high fluence/low temperature plasma cannot be obtained. Important key issues to be resolved according to PWI studies are the tritium retention, dust production, resilience to large steady-state fluences, transient loads, surface erosion, material redeposition and neutron damage. Some linear plasma simulators come close to the very high fluences expected in ITER and DEMO such as PSI-2; PISCES-B; NAGDIS-II, pilot-PSI and MAGNUM-PSI. The plasmatron VISION I to be installed in Mol, will have the capability to investigate mixed materials (with Be/T contaminations) and in the long term neutron activated samples. The equipment is meant to study plasma-wall interaction, in particular the interaction with hydrogen isotopes. The facility is capable to produce relatively cold self-sustained volumetric plasmas with a high plasma flux density at the target of about 1020–1021 ions/m2.s. The plasmatron has a volume of 18litres, a target diameter of ~25cm and modular ion energies in the range of 20-500eV.