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Influence of Pulsed Beam-Plasma Impact on a Tungsten–Copper Pseudoalloy in the Plasma Focus Device
The results of a study of the combined effect on the W–Cu pseudoalloy of pulsed flows of deuterium
ions with a power density of qi ≈ 1 × 109 W/cm2 at an exposure duration of τi = 20 ns and deuterium
plasma with parameters qpl ≈ 1 × 108 W/cm2 and τpl = 20 ns generated in the “Vikhr” Plasma Focus installation
are presented. It is shown that in the implemented mode of irradiation the nature of the damage to the
surface layer of the tested material depends on the state of the surface of the irradiated samples and the number
of pulsed impacts of energy flows. The impact of pulsed irradiation on the polished surface of pseudoalloy
samples leads to the appearance of extended copper drops on the tungsten surface and to the formation of
many pores, which are observed both in Cu drops and in the W matrix. In addition, microcracks appear on
the W surface, as well as islands of a copper film of arbitrary configuration. Repeated irradiation of samples
of the studied material with an unpolished surface leads to the formation of chains of tungsten droplets
located in the upper parts of extended ridges formed during grinding of the original samples. Bursting bubbles
are also visible on the irradiated surface, which arise as a result of the boiling of copper inclusions and a copper
film deposited on tungsten. Clusters of such bubbles are often localized along ridges on the tungsten surface.
The results obtained are discussed using numerical calculations and analysis of the thermal effect on the considered
pseudoalloy under pulsed irradiation.