An overview of cold plasma interactions with tungsten and titanium surfaces for laboratory investigations relevant to fusion research studies

This study reports results on the interactions of H2, D2, He, and Ar plasmas with W and Ti surfaces. We employed the Hollow-Cathode and Microjet configurations for tests on plasma-W and Ti surface interactions, as well as for the collection of tungsten dust at various distances. Consequently, the exposed tungsten and titanium materials are examined for surface alterations (blister development, dust generation, erosion, or nano-structuring), as well as crystallinity, in relation to the duration of plasma exposure. A specific approach was employed to provide a mechanism for acquiring fusion-relevant tungsten surfaces in hydrogen and deuterium plasma discharges. Also, experiments present the potential to achieve a novel tungsten morphology, namely a dandelion-like structure, through the application of helium plasma, along with Ti-shaped cones, by using Ar plasma. Dedicated techniques (SEM, XRD, Contact Profilometry, Hardness tests, TDS, OES, and Langmuir Probes) investigated both materials and plasmas.