Deuterium trapping properties of plasma sprayed tungsten layers irradiated by low energy and high flux plasma

Deuterium retention and trapping in tungsten plasma sprayed layers after low energy plasma irradiation was investigated by means of thermal desorption technique. Plasma irradiation at low temperatures (<650 K) showed the retention and trapping similar to polycrystalline tungsten material. On the other hand, irradiation at high temperatures (>650 K) showed significant increase of the retention in the plasma sprayed layers contrary to the polycrystalline material. Thermal desorption spectra showed extremely high temperatures of the peak positions which are non-typical for the tungsten materials. The possible reasons for such high deuterium retention in the plasma sprayed layers after irradiation at high temperatures and the possible trapping mechanisms are discussed