[en] The paper is focused on the problem of understanding key items of high heat flux plasma-material interaction during abnormal events: the net power flux that reached the target surface and the nature of the target erosion. As to first the results of direct measurements of visible radiation (Δλ=400-800 nm) flux on the target surface are presented. It is shown that visible radiation power flux emitted inside spectral range Δλ=400-700 nm can be characterised by the level of P_R≤1 GW/m² typical of experiments performed at the VIKA facility during irradiation power of P_irr∼80 GW/m². It is also shown that the existence of the strong guide magnetic field of B∼2 T results in a change in the behaviour and microstructure of the (Al) metal melt layer