| Summary: | Specimens of materials for prospective use in chambers of nuclear fusion reactors with
inertial plasma confinement, namely, W, ODS steels, Eurofer 97 steel, a number of
ceramics, etc., have been irradiated by dense plasma focus devices and a laser in the
Q-switched mode of operation with a wide range of parameters, including some that
noticeably exceeded those expected in reactors. By means of 1-ns laser interferometry and
neutron measurements, the characteristics of plasma streams and fast ion beams, as well as
the dynamics of their interaction with solid-state targets, have been investigated. 3D
profilometry, optical and scanning electron microscopy, atomic emission spectroscopy,
X-ray elemental and structural analyses, and precise weighing of specimens before and
after irradiation have provided data on the roughening threshold and the susceptibility to
damage of the materials under investigation. Analysis of the results, together with
numerical modeling, has revealed the important role of shock waves in the damage
processes. It has been shown that a so-called integral damage factor may be used only
within restricted ranges of the irradiation parameters. It has also been found that in the
irradiation regime with well-developed gasdynamic motion of secondary plasma, the overall
amount of radiation energy is spent preferentially either on removing large masses of cool
matter from the material surface or on heating a small amount of plasma to high
temperature (and, consequently, imparting to it a high velocity), depending on the power
flux density and characteristics of the pulsed irradiation.
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