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Nanostructured carbon materials have increasingly attracted the interest of the scientific community, because of their
fascinating physical properties and potential applications in high-tech devices. In the current ITER design, the tiles made
of carbon fiber composites (CFCs) are foreseen for the strike point zone and tungsten (W) for other parts of the divertor
region. This choice is a compromise based mainly on experience with individual materials in many different tokamaks.
Also Carbon-Aluminum composites are the candidate material for the First Wall in ITER.
In order to prepare nanostructured carbon-aluminum nanocomposite for the divertor part in fusion applications, the
original method thermionic vacuum arc (TVA) was used in two electronic guns configuration. One of the main
advantages of this technology is the bombardment of the growing thin film just by the ions of the depositing film.
Moreover, the energy of ions can be controlled. Thermo-electrons emitted by an externally heated cathode and focused
by a Wehnelt focusing cylinder are strongly accelerated towards the anode whose material is evaporated and bright
plasma is ignited by a high voltage DC supply.
The nanostructured C-Al films were characterized by Scanning Electron Microscopy (SEM), Transmission Electron
Microscopy (TEM). Tribological properties in dry sliding were evaluated using a CSM ball-on-disc tribometer. The
carbon - aluminum films were identified as a nanocrystals complex (from 2nm to 50 nm diameters) surrounded by
amorphous structures with a strong graphitization tendency, allowing the creating of adherent and wear resistant films.
The friction coefficients (0.1 - 0.2, 0.5) of the C-Al coatings was decreased more than 2-5 times in comparison with the
uncoated substrates proving excellent tribological properties. C-Al nanocomposites coatings were designed to have
excellent tribological properties while the structure is composed by nanocrystals complex surrounded by amorphous
structures with a strong graphitization tendency, allowing the creating of adherent and wear resistant films.
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