Damage to the Surface Layer of Inconel 718 Alloy by Pulsed Beam-Plasma Flows

Inorganic Materials: Applied Research. 2024. Vol. 15. No. 3. P. 596–605.

Borovitskaya I. V., Demin A. S., Komolova O. A., Latyshev S. V., Maslyaev S. A., Monakhov I., Morozov E. V., Pimenov V. N., Sasinovskaya I. P., Bondarenko G.G., Gaydar A. I., Logachev I. A.

Damage to the surface layer of the Inconel 718 alloy, manufactured by selective laser melting using
additive technology followed by heat treatment, is studied under conditions of repeated pulsed exposure to
flows of helium ions and helium plasma under two irradiation modes in the Vikhr Plasma Focus installation:
in a soft mode with energy flux density q0 = 2 × 108 W/cm2 and pulse duration τ = 50 ns and in a hard mode
with q0 = 1.5 × 109 W/cm2 and τ = 25 ns. The number of pulses in the experiments was N = 10 and 20. Irradiation
in a soft mode forms a microstructure containing pores on the layer surface, and with more severe
energy exposure, surface microcracks and blisters with destroyed shells are formed. With an increase in the
energy flux density, the surface layer erosion intensity (mass loss per pulse) increased. The nature of this phenomenon is determined by the processes of cleaning the surface layer of an alloy from impurity elements
adsorbed from the external environment before irradiation, as well as the deposition of elements of functional
materials and working gas impurities on the irradiated surface. Features of cellular microstructure formation
of the surface layer (SL) of an alloy under study under the realized conditions of beam-plasma influences have
been revealed. Using the numerical modeling method, the redistribution of the shares of energy absorbed by
the material, spent on evaporation and melting of the irradiated surface layer (SL), in comparable irradiation
modes was established.

Keywords: damage, плазма, микроструктура, plasma, microstructure, повреждаемость