The tungsten surface structure was analyzed after the test in the QSPA-T under heat loads relevant to those expected in the ITER during disruptions. Repeated pulses lead to the melting and the recrystallization of the tungsten surface layer of ~50 μm thickness. The recrystallized layer has the same texture as the original structure with the orientation <100> which is normal to the surface, at the same time the grains' sizes in the recrystallized layer are much larger. There is an interface layer between the original structure and the recrystallized layer. The interface layer has a random grains' orientation and ~50 μm thickness. The texture of this layer differs considerably from the original tungsten structure. The cracks which are normal to the surface were observed in the recrystallyzed layer as well as the cracks which are parallel to the surface at the depth up to 300 μm. Such cracks can result in the brittle destruction which is a hazard for the full tungsten divertor of the ITER. The theoretical analysis of the crack formation reasons and a possible consequence for the ITER is given.

The structure of lithium deposited specimens at the T-10 tokamak vessel after examination of lithium capillary porous system were analysed. Scanning electron microscopy have been used to analyse the deposits. Composites of lithium carbonate LixCOy have been found by analysis. Plasma irradiation of these lithium specimens have been carried out in the PLM plasma device with plasma parameters similar to the tokamak divertor plasma. Stationary plasma load up to 1 MW/m2 during 200 minutes in the PLM provided the change of surface morphology revealed by post-mortem analysis.

In edge plasma in the Large Helical Device (LHD), incoherent fluctuations with intermittent density bursts were observed with a two-dimensional lithium beam probe that can measure electron density and its fluctuation two-dimensionally. Statistical analysis using a probability denstiy function (PDF) showed that those bursts have the characteristics of blobs, which have been observed in tokamaks. Two-dimensional PDF analysis indicates that the blobs originate in the ergodic layer outside the last closed flux surface and move to the outer region. Wavelet analysis showed that the direction of blob propagation is not always outward but is sometimes in arbitrary directions. These characteristics may be a result of the complicated magnetic field structure of the heliotron configuration.

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Plasma tests of a tin capillary-porous system (CPS) were carried out on the PLM plasma device. This CPS is made similar to the lithium CPS used in experiments in tokamaks T-10, T-11M. The CPS system was immersed in the PLM plasma device and tested for 3 hours in a stationary helium discharge with plasma load of 1 MW / m2. The tin CPS has not damaged after such plasma load suggesting it as plasma facing component in fusion reactors and plasma engines.